diff --git a/apps/arstack_studio/CMakeLists.txt b/apps/arstack_studio/CMakeLists.txt
index ddfed8eb6..41a31383a 100644
--- a/apps/arstack_studio/CMakeLists.txt
+++ b/apps/arstack_studio/CMakeLists.txt
@@ -93,6 +93,9 @@ qt_add_qml_module(arstack_studio
         qml/RibbonAction.qml
         qml/CalmButton.qml
         qml/NumericField.qml
+        qml/DarkComboBox.qml
+        qml/DarkCheckBox.qml
+        qml/SignalQuickMenu.qml
         qml/StateBadge.qml
         qml/ProfileInspector.qml
         qml/ConfigurationHub.qml
@@ -170,6 +173,13 @@ target_compile_definitions(arstack_session_harness PRIVATE
     ARSTACK_STUDIO_VERSION="${PROJECT_VERSION}"
 )
 
+# Dedicated ARStack Studio icon shared by Qt window, Windows PE, and Inno.
+qt_add_resources(arstack_studio "studio_branding"
+    PREFIX "/studio"
+    BASE "${CMAKE_CURRENT_LIST_DIR}/../../assets/studio_icon"
+    FILES "${CMAKE_CURRENT_LIST_DIR}/../../assets/studio_icon/favicon.ico"
+)
 if(WIN32)
+    target_sources(arstack_studio PRIVATE src/StudioIcon.rc)
     set_target_properties(arstack_studio PROPERTIES WIN32_EXECUTABLE TRUE)
 endif()
\ No newline at end of file
diff --git a/apps/arstack_studio/packaging/ARStackStudio.iss b/apps/arstack_studio/packaging/ARStackStudio.iss
index d0013daf6..4d97486e0 100644
--- a/apps/arstack_studio/packaging/ARStackStudio.iss
+++ b/apps/arstack_studio/packaging/ARStackStudio.iss
@@ -36,6 +36,8 @@ UninstallDisplayName={#ProductName}
 DefaultDirName={localappdata}\Programs\{#ProductFolder}
 DefaultGroupName={#ProductName}
 OutputBaseFilename={#ProductOutput}
+SetupIconFile=..\..\..\assets\studio_icon\favicon.ico
+UninstallDisplayIcon={app}\ARStackStudio.exe
 PrivilegesRequired=lowest
 ArchitecturesAllowed=x64compatible
 CloseApplications=yes
diff --git a/apps/arstack_studio/qml/ConfigurationHub.qml b/apps/arstack_studio/qml/ConfigurationHub.qml
index 417f86d58..af6566a0c 100644
--- a/apps/arstack_studio/qml/ConfigurationHub.qml
+++ b/apps/arstack_studio/qml/ConfigurationHub.qml
@@ -75,7 +75,7 @@ Item {
                     font.weight: Font.DemiBold
                 }
                 Label {
-                    text: "Firmware recovery, engineering profile, waveform and timing tools"
+                    text: "SIMULATION LAB  /  4I+4V · PTP · Firmware · Diagnostics"
                     color: hub.theme.muted
                     font.family: hub.uiFont
                     font.pixelSize: 11
@@ -121,10 +121,10 @@ Item {
                 border.width: 1
                 border.color: hub.theme.lineSoft
             }
-            ExpertTab { text: "Injection" }
+            ExpertTab { text: "Signal profile" }
             ExpertTab { text: "Firmware" }
-            ExpertTab { text: "Waveform" }
-            ExpertTab { text: "Timing" }
+            ExpertTab { text: "Wave shaping" }
+            ExpertTab { text: "PTP / Sync" }
             ExpertTab { text: "Device" }
         }
 
diff --git a/apps/arstack_studio/qml/DarkCheckBox.qml b/apps/arstack_studio/qml/DarkCheckBox.qml
new file mode 100644
index 000000000..fc9e5ef9b
--- /dev/null
+++ b/apps/arstack_studio/qml/DarkCheckBox.qml
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+import QtQuick
+import QtQuick.Controls
+
+CheckBox {
+    id: control
+    property var theme
+    property string uiFont: "Inter"
+    font.family: uiFont
+    font.pixelSize: 11
+    implicitHeight: 29
+    spacing: 8
+    indicator: Rectangle {
+        implicitWidth: 17
+        implicitHeight: 17
+        x: 1
+        y: (control.height - height) / 2
+        radius: 4
+        color: control.checked ? control.theme.accent : control.theme.surface2
+        border.width: 1
+        border.color: control.checked ? control.theme.accent : control.theme.line
+        Text {
+            anchors.centerIn: parent
+            text: "✓"
+            visible: control.checked
+            color: control.theme.bg
+            font.pixelSize: 12
+            font.weight: Font.Bold
+        }
+    }
+    contentItem: Text {
+        text: control.text
+        font: control.font
+        color: control.enabled ? control.theme.textSoft : control.theme.muted
+        verticalAlignment: Text.AlignVCenter
+        leftPadding: control.indicator.width + control.spacing
+    }
+}
diff --git a/apps/arstack_studio/qml/DarkComboBox.qml b/apps/arstack_studio/qml/DarkComboBox.qml
new file mode 100644
index 000000000..eb0bae4c5
--- /dev/null
+++ b/apps/arstack_studio/qml/DarkComboBox.qml
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+import QtQuick
+import QtQuick.Controls
+
+ComboBox {
+    id: control
+    property var theme
+    property string uiFont: "Inter"
+    implicitWidth: 180
+    implicitHeight: 35
+    font.family: uiFont
+    font.pixelSize: 11
+    hoverEnabled: true
+    contentItem: Text {
+        text: control.displayText
+        color: control.enabled ? control.theme.text : control.theme.muted
+        font: control.font
+        verticalAlignment: Text.AlignVCenter
+        elide: Text.ElideRight
+        leftPadding: 11
+        rightPadding: 30
+    }
+    indicator: Text {
+        text: "⌄"
+        color: control.theme.textSoft
+        font.pixelSize: 18
+        anchors.verticalCenter: parent.verticalCenter
+        anchors.right: parent.right
+        anchors.rightMargin: 12
+    }
+    background: Rectangle {
+        radius: 7
+        color: control.hovered ? control.theme.raisedHover : control.theme.surface2
+        border.width: 1
+        border.color: control.activeFocus ? control.theme.accent : control.theme.line
+    }
+    delegate: ItemDelegate {
+        id: item
+        required property int index
+        // textAt resolves QStringList and QAbstractItemModel textRole.
+        width: control.width
+        height: 35
+        highlighted: control.highlightedIndex === index
+        contentItem: Text {
+            text: control.textAt(item.index)
+            font: control.font
+            color: control.theme.text
+            leftPadding: 9
+            verticalAlignment: Text.AlignVCenter
+            elide: Text.ElideRight
+        }
+        background: Rectangle {
+            radius: 5
+            color: item.highlighted ? control.theme.accentSoft
+                  : item.hovered ? control.theme.raisedHover : "transparent"
+        }
+    }
+    popup: Popup {
+        y: control.height + 3
+        width: control.width
+        implicitHeight: Math.min(contentItem.implicitHeight + 10, 220)
+        padding: 5
+        contentItem: ListView {
+            implicitHeight: contentHeight
+            clip: true
+            model: control.popup.visible ? control.delegateModel : null
+            currentIndex: control.highlightedIndex
+            ScrollIndicator.vertical: ScrollIndicator {}
+        }
+        background: Rectangle {
+            radius: 8
+            color: control.theme.raised
+            border.width: 1
+            border.color: control.theme.line
+        }
+    }
+}
diff --git a/apps/arstack_studio/qml/DeviceExpertPanel.qml b/apps/arstack_studio/qml/DeviceExpertPanel.qml
index 0470ddf30..3963d0e32 100644
--- a/apps/arstack_studio/qml/DeviceExpertPanel.qml
+++ b/apps/arstack_studio/qml/DeviceExpertPanel.qml
@@ -53,7 +53,9 @@ SurfacePanel {
 
         RowLayout {
             Layout.fillWidth: true
-            ComboBox {
+            DarkComboBox {
+                theme: panel.theme
+                uiFont: panel.uiFont
                 id: recoveryPort
                 Layout.preferredWidth: 170
                 model: panel.device.ports
diff --git a/apps/arstack_studio/qml/Main.qml b/apps/arstack_studio/qml/Main.qml
index 4da38730e..01b538345 100644
--- a/apps/arstack_studio/qml/Main.qml
+++ b/apps/arstack_studio/qml/Main.qml
@@ -298,6 +298,52 @@ ApplicationWindow {
         return true
     }
 
+    // Three-phase lab shortcuts; neutral is deliberately untouched.
+    // Existing live setpoint session owns the serial writer and ordering.
+    function quickSetGroup(group, row, action) {
+        if (row < 0 || row > 2) return false
+        var model = groupModel(group)
+        var anchor = model.get(row)
+        var i
+        if (action === "equal_value") {
+            if (!validMagnitude(group, anchor.magnitude)) return false
+            for (i = 0; i < 3; ++i) model.setProperty(i, "magnitude", anchor.magnitude)
+        } else if (action === "equal_angle") {
+            if (signalFrequency <= 0 || !validPhase(anchor.phase)) return false
+            for (i = 0; i < 3; ++i) model.setProperty(i, "phase", anchor.phase)
+        } else if (action === "balance_angle") {
+            if (signalFrequency <= 0 || !validPhase(anchor.phase)) return false
+            var a = anchor.phase + (row === 1 ? 120 : row === 2 ? -120 : 0)
+            var angles = [normalizedAngle(a), normalizedAngle(a - 120), normalizedAngle(a + 120)]
+            for (i = 0; i < 3; ++i) model.setProperty(i, "phase", angles[i])
+        } else return false
+        selectSignal(group, row)
+        var submitted = false
+        if (workflowBar.session && workflowBar.session.liveControlReady) {
+            var batch = []
+            for (i = 0; i < 3; ++i) {
+                var channel = model.get(i)
+                batch.push({
+                    signalId: channel.signalId,
+                    magnitude: channel.magnitude,
+                    phase: channel.phase,
+                    quality: Number(channel.quality) >>> 0
+                })
+            }
+            submitted = workflowBar.session.requestSetSignalsBatch(
+                batch, currentScale, voltageScale)
+            if (!submitted) {
+                showMessage("ABC changed locally; complete live batch rejected. Copy diagnostics.", true)
+                return false
+            }
+        }
+        showMessage((group === 0 ? "Current" : "Voltage") + " ABC: " +
+                    (action === "equal_value" ? "Equal Value" : action === "equal_angle" ? "Equal Angle" : "Balance 120°") +
+                    (submitted ? " · 3 commands submitted together" : " · offline preview") +
+                    " · neutral unchanged", false)
+        return true
+    }
+
     function applyAllSignals() {
         if (!workflowBar.session || !workflowBar.session.liveControlReady) return
         workflowBar.session.requestSetFrequency(signalFrequency)
@@ -472,10 +518,10 @@ ApplicationWindow {
 
     Window {
         id: configurationWindow
-        width: 760
-        height: 780
-        minimumWidth: 640
-        minimumHeight: 660
+        width: 860
+        height: 750
+        minimumWidth: 700
+        minimumHeight: 620
         visible: false
         title: "ARStack Studio · Advanced"
         color: studioTheme.bg
@@ -485,27 +531,17 @@ ApplicationWindow {
             configurationWindow.hide()
         }
 
-        DockFrame {
+        ConfigurationHub {
+            id: profilePanel
             anchors.fill: parent
-            anchors.margins: 10
+            anchors.margins: 18
             theme: studioTheme
-            titleText: "Advanced"
-            statusText: device.deviceVerified ? "DEVICE CONNECTED" : "OFFLINE"
+            controller: root
+            device: device
+            profiles: sclProfiles
+            session: workflowBar.session
             uiFont: root.uiFont
             monoFont: root.monoFont
-            closable: false
-
-            ConfigurationHub {
-                id: profilePanel
-                anchors.fill: parent
-                theme: studioTheme
-                controller: root
-                device: device
-                profiles: sclProfiles
-                session: workflowBar.session
-                uiFont: root.uiFont
-                monoFont: root.monoFont
-            }
         }
     }
 
@@ -726,7 +762,8 @@ ApplicationWindow {
                                 CalmButton { theme: studioTheme; uiFont: root.uiFont; text: "50"; implicitWidth: 44; onClicked: root.setFrequencyValue(50) }
                                 CalmButton { theme: studioTheme; uiFont: root.uiFont; text: "60"; implicitWidth: 44; onClicked: root.setFrequencyValue(60) }
                                 Rectangle { width: 1; height: 24; color: studioTheme.lineSoft }
-                                CheckBox {
+                                DarkCheckBox {
+                                    theme: studioTheme
                                     enabled: root.signalFrequency > 0
                                     checked: root.phaseLink
                                     text: "3-phase link"
diff --git a/apps/arstack_studio/qml/ProfileInspector.qml b/apps/arstack_studio/qml/ProfileInspector.qml
index cff19bbce..273d40e0d 100644
--- a/apps/arstack_studio/qml/ProfileInspector.qml
+++ b/apps/arstack_studio/qml/ProfileInspector.qml
@@ -117,7 +117,9 @@ SurfacePanel {
                 font.letterSpacing: 1.0
             }
 
-            ComboBox {
+            DarkComboBox {
+                theme: panel.theme
+                uiFont: panel.uiFont
                 Layout.fillWidth: true
                 model: panel.profiles
                 textRole: "control"
@@ -308,7 +310,9 @@ SurfacePanel {
                     wrapMode: Text.WordWrap
                 }
 
-                ComboBox {
+                DarkComboBox {
+                theme: panel.theme
+                uiFont: panel.uiFont
                     id: profileFamilySelector
                     Layout.fillWidth: true
                     enabled: panel.session && panel.session.engineeringEditable
diff --git a/apps/arstack_studio/qml/PtpExpertPanel.qml b/apps/arstack_studio/qml/PtpExpertPanel.qml
index 80d1de77f..419509eb1 100644
--- a/apps/arstack_studio/qml/PtpExpertPanel.qml
+++ b/apps/arstack_studio/qml/PtpExpertPanel.qml
@@ -2,6 +2,7 @@
 import QtQuick
 import QtQuick.Controls
 import QtQuick.Layouts
+import ARStack.Studio 1.0
 
 SurfacePanel {
     id: panel
@@ -12,6 +13,9 @@ SurfacePanel {
     property string monoFont: "Inter"
     property var roleValues: ["SOURCE", "RECEIVER", "MONITOR"]
     property bool advancedVisible: false
+    // Keep PTP role changes in the existing verified serial transaction.
+    readonly property bool controlReady: panel.session && panel.device.ptpAvailable &&
+        !panel.session.updatingFirmware
     readonly property bool startPending: panel.device && panel.device.ptpStarting
 
     function roleIndex(role) {
@@ -45,7 +49,7 @@ SurfacePanel {
     }
 
     function startSelectedMode() {
-        if (!panel.session || !panel.device.ptpAvailable) return
+        if (!panel.controlReady || panel.startPending || panel.device.ptpRunning) return
         var role = panel.roleValues[modeCombo.currentIndex]
         if (!panel.session.requestStartPtpConfigured(role, panel.ptpProfile())) {
             if (panel.controller) panel.controller.showMessage("PTP start blocked. See the Timing status for details.", true)
@@ -109,6 +113,50 @@ SurfacePanel {
                     }
                 }
                 Item { Layout.fillWidth: true }
+                Switch {
+                    id: ptpToggle
+                    text: "PTP"
+                    checked: panel.device.ptpRunning
+                    enabled: panel.controlReady && !panel.startPending
+                    onClicked: {
+                        // AbstractButton toggles its local checked property before
+                        // the async firmware ACK. Restore the only authoritative
+                        // device-state binding immediately: rejected START must
+                        // never leave this switch falsely showing ON.
+                        var requestedOn = checked
+                        checked = Qt.binding(function() { return panel.device.ptpRunning })
+                        if (requestedOn) panel.startSelectedMode()
+                        else panel.session.requestStopPtp()
+                    }
+                    font.family: panel.uiFont
+                    font.pixelSize: 11
+                    indicator: Rectangle {
+                        implicitWidth: 42
+                        implicitHeight: 24
+                        x: 0
+                        y: (ptpToggle.height - height) / 2
+                        radius: 12
+                        color: ptpToggle.checked ? panel.theme.greenSoft : panel.theme.raised
+                        border.width: 1
+                        border.color: ptpToggle.checked ? panel.theme.green : panel.theme.line
+                        Rectangle {
+                            width: 16
+                            height: 16
+                            radius: 8
+                            x: ptpToggle.checked ? 22 : 3
+                            anchors.verticalCenter: parent.verticalCenter
+                            color: ptpToggle.checked ? panel.theme.green : panel.theme.textSoft
+                            Behavior on x { NumberAnimation { duration: 110 } }
+                        }
+                    }
+                    contentItem: Text {
+                        text: "PTP"
+                        font: ptpToggle.font
+                        color: panel.theme.textSoft
+                        leftPadding: ptpToggle.indicator.width + 9
+                        verticalAlignment: Text.AlignVCenter
+                    }
+                }
                 StateBadge {
                     theme: panel.theme
                     monoFont: panel.uiFont
@@ -143,10 +191,12 @@ SurfacePanel {
                             font.pixelSize: 9
                             font.weight: Font.DemiBold
                         }
-                        ComboBox {
+                        DarkComboBox {
+                            theme: panel.theme
+                            uiFont: panel.uiFont
                             id: modeCombo
                             Layout.fillWidth: true
-                            model: ["Provide PTP timing", "Follow external PTP", "Monitor PTP only"]
+                            model: ["Source · provide lab time", "Follower · auto-discover GM", "Monitor · listen only"]
                             currentIndex: panel.roleIndex(panel.activeRole)
                             enabled: panel.session && panel.device.ptpAvailable && !panel.device.ptpRunning && !panel.startPending && !panel.session.updatingFirmware
                             font.family: panel.uiFont
@@ -161,7 +211,7 @@ SurfacePanel {
                             text: modeCombo.currentIndex === 0
                                 ? "Board sends Announce + hardware-timestamped two-step Sync/Follow_Up."
                                 : modeCombo.currentIndex === 1
-                                    ? "Board follows an external PTP source and reports measured clock lock."
+                                    ? "Automatically discovers a grandmaster; a server IP is not required for L2 PTP."
                                     : "Board listens to PTP without transmitting or disciplining its clock."
                             wrapMode: Text.WordWrap
                             color: panel.theme.textSoft
@@ -170,14 +220,14 @@ SurfacePanel {
                         }
                         Label {
                             text: modeCombo.currentIndex === 0
-                                ? "PTP TX does not by itself change SV smpSynch."
+                                ? "PTP transmit does not automatically phase-lock SMV."
                                 : modeCombo.currentIndex === 1
                                     ? "AUTO smpSynch follows measured receiver evidence only."
                                     : "Useful for observing timing traffic without changing the network."
                             wrapMode: Text.WordWrap
                             color: panel.theme.muted
                             font.family: panel.uiFont
-                            font.pixelSize: 8
+                            font.pixelSize: 10
                         }
                     }
                 }
@@ -214,9 +264,17 @@ SurfacePanel {
                     enabled: panel.session && panel.device.deviceVerified && !panel.session.updatingFirmware
                     onClicked: panel.session.requestPtpRefresh()
                 }
+                CalmButton {
+                    theme: panel.theme
+                    uiFont: panel.uiFont
+                    text: "Copy diagnostics"
+                    enabled: panel.session
+                    onClicked: StudioClipboard.copyText(panel.session.diagnosticsText())
+                }
                 Item { Layout.fillWidth: true }
-                CheckBox {
-                    text: "Advanced settings"
+                DarkCheckBox {
+                    theme: panel.theme
+                    text: "Protocol settings"
                     checked: panel.advancedVisible
                     onToggled: panel.advancedVisible = checked
                     font.family: panel.uiFont
@@ -239,11 +297,11 @@ SurfacePanel {
                     columnSpacing: 14
                     rowSpacing: 6
 
-                    Label { text: panel.sourceRole ? "Announce TX" : "Announce RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
-                    Label { text: panel.sourceRole ? "Sync TX" : "Sync RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
-                    Label { text: panel.sourceRole ? "Follow_Up TX" : "Follow_Up RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
-                    Label { text: panel.sourceRole ? "Pdelay TX" : "Pdelay RX / Req"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
-                    Label { text: panel.sourceRole ? "TX failures" : "Accepted / rejected"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
+                    Label { text: panel.sourceRole ? "Announce TX" : "Announce RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
+                    Label { text: panel.sourceRole ? "Sync TX" : "Sync RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
+                    Label { text: panel.sourceRole ? "Follow_Up TX" : "Follow_Up RX"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
+                    Label { text: panel.sourceRole ? "Pdelay TX" : "Pdelay RX / Req"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
+                    Label { text: panel.sourceRole ? "TX failures" : "Accepted / rejected"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
 
                     Label { text: panel.sourceRole ? panel.device.ptpAnnounceSent : panel.device.ptpRxAnnounce; color: panel.theme.text; font.family: panel.monoFont; font.pixelSize: 15; font.weight: Font.DemiBold }
                     Label { text: panel.sourceRole ? panel.device.ptpSyncSent : panel.device.ptpRxSync; color: panel.theme.text; font.family: panel.monoFont; font.pixelSize: 15; font.weight: Font.DemiBold }
@@ -278,17 +336,62 @@ SurfacePanel {
                     anchors.fill: parent
                     anchors.margins: 10
                     columns: 4
-                    Label { text: "Discipline"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
+                    Label { text: "Discipline"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
                     Label { text: panel.device.ptpDiscipline === "LOCKED" ? "LOCKED (board)" : panel.device.ptpDiscipline; color: panel.theme.amber; font.family: panel.monoFont; font.pixelSize: 10; font.weight: Font.DemiBold }
-                    Label { text: "Selected source"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
+                    Label { text: "Selected source"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
                     Label { text: panel.device.ptpSource === "NONE" ? "—" : panel.device.ptpSource; color: panel.theme.text; font.family: panel.monoFont; font.pixelSize: 9 }
-                    Label { text: "Offset"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
+                    Label { text: "Offset"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
                     Label { text: panel.device.ptpOffsetNs === "NA" ? "—" : panel.device.ptpOffsetNs + " ns"; color: panel.theme.text; font.family: panel.monoFont; font.pixelSize: 10 }
-                    Label { text: "Path delay"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8 }
+                    Label { text: "Path delay"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 10 }
                     Label { text: panel.device.ptpPathDelayNs === "NA" ? "—" : panel.device.ptpPathDelayNs + " ns"; color: panel.theme.text; font.family: panel.monoFont; font.pixelSize: 10 }
                 }
             }
 
+            Rectangle {
+                Layout.fillWidth: true
+                implicitHeight: 134
+                radius: 8
+                color: panel.theme.panelAlt
+                border.width: 1
+                border.color: panel.theme.lineSoft
+                ColumnLayout {
+                    anchors.fill: parent
+                    anchors.margins: 12
+                    spacing: 6
+                    Rectangle { Layout.fillWidth: true; height: 1; color: panel.theme.lineSoft }
+                Label { text: "SV output flag · lab simulation"; color: panel.theme.text; font.family: panel.uiFont; font.pixelSize: 12; font.weight: Font.DemiBold }
+                RowLayout {
+                    Layout.fillWidth: true
+                    DarkComboBox {
+                        theme: panel.theme
+                        uiFont: panel.uiFont
+                        Layout.fillWidth: true
+                        model: ["AUTO · measured only", "0 · Unsynchronized", "1 · Local (simulated)", "2 · Global (simulated)"]
+                        currentIndex: panel.syncIndex(panel.device.smpSynchMode)
+                        enabled: panel.session && panel.device.deviceVerified && !panel.session.updatingFirmware
+                        font.family: panel.uiFont
+                        font.pixelSize: 9
+                        onActivated: panel.session.requestSmpSynch(["AUTO", "0", "1", "2"][currentIndex])
+                    }
+                    StateBadge {
+                        theme: panel.theme
+                        monoFont: panel.uiFont
+                        state: "smpSynch=" + panel.device.smpSynchValue
+                            + (panel.device.smpSynchSimulated ? " SIMULATED" : panel.device.smpSynchMeasured ? " MEASURED" : " SAFE")
+                        stateColor: panel.device.smpSynchSimulated ? panel.theme.amber : panel.device.smpSynchMeasured ? panel.theme.green : panel.theme.muted
+                    }
+                }
+                Label {
+                    Layout.fillWidth: true
+                    text: "PTP observed does not imply the SV sample clock is phase-locked. Lab override sets advertised metadata only."
+                    wrapMode: Text.WordWrap
+                    color: panel.theme.textSoft
+                    font.family: panel.uiFont
+                    font.pixelSize: 10
+                }
+                }
+            }
+
             ColumnLayout {
                 visible: panel.advancedVisible
                 Layout.fillWidth: true
@@ -310,11 +413,13 @@ SurfacePanel {
                     NumericField { id: announceField; theme: panel.theme; monoFont: panel.uiFont; text: "1000"; validator: IntValidator { bottom: 100; top: 10000 } }
                     Label { text: "Sync interval (ms)"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 9 }
                     NumericField { id: syncField; theme: panel.theme; monoFont: panel.uiFont; text: "1000"; validator: IntValidator { bottom: 20; top: 5000 } }
-                    CheckBox { id: vlanCheck; text: "VLAN"; font.family: panel.uiFont; font.pixelSize: 9 }
+                    DarkCheckBox {
+                        theme: panel.theme; id: vlanCheck; text: "VLAN"; font.family: panel.uiFont; font.pixelSize: 9 }
                     NumericField { id: vlanField; enabled: vlanCheck.checked; theme: panel.theme; monoFont: panel.uiFont; text: "100"; validator: IntValidator { bottom: 1; top: 4094 } }
                     Label { text: "VLAN PCP"; color: panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 9 }
                     NumericField { id: pcpField; enabled: vlanCheck.checked; theme: panel.theme; monoFont: panel.uiFont; text: "4"; validator: IntValidator { bottom: 0; top: 7 } }
-                    CheckBox { id: pdelayCheck; text: "Peer-delay response"; checked: true; font.family: panel.uiFont; font.pixelSize: 9 }
+                    DarkCheckBox {
+                        theme: panel.theme; id: pdelayCheck; text: "Peer-delay response"; checked: true; font.family: panel.uiFont; font.pixelSize: 9 }
                     CalmButton {
                         theme: panel.theme
                         uiFont: panel.uiFont
@@ -327,35 +432,6 @@ SurfacePanel {
                     }
                 }
 
-                Rectangle { Layout.fillWidth: true; height: 1; color: panel.theme.lineSoft }
-                Label { text: "SV synchronization flag · lab / interoperability"; color: panel.theme.text; font.family: panel.uiFont; font.pixelSize: 12; font.weight: Font.DemiBold }
-                RowLayout {
-                    Layout.fillWidth: true
-                    ComboBox {
-                        Layout.fillWidth: true
-                        model: ["AUTO — measured PTP only", "0 — Not synchronized", "1 — Local synchronized (simulation)", "2 — Global synchronized (simulation)"]
-                        currentIndex: panel.syncIndex(panel.device.smpSynchMode)
-                        enabled: panel.session && panel.device.deviceVerified && !panel.session.updatingFirmware
-                        font.family: panel.uiFont
-                        font.pixelSize: 9
-                        onActivated: panel.session.requestSmpSynch(["AUTO", "0", "1", "2"][currentIndex])
-                    }
-                    StateBadge {
-                        theme: panel.theme
-                        monoFont: panel.uiFont
-                        state: "smpSynch=" + panel.device.smpSynchValue
-                            + (panel.device.smpSynchSimulated ? " SIMULATED" : panel.device.smpSynchMeasured ? " MEASURED" : " SAFE")
-                        stateColor: panel.device.smpSynchSimulated ? panel.theme.amber : panel.device.smpSynchMeasured ? panel.theme.green : panel.theme.muted
-                    }
-                }
-                Label {
-                    Layout.fillWidth: true
-                    text: "PTP Source transmission is not proof that the SV clock is externally synchronized. AUTO stays fail-closed unless receiver discipline is measured."
-                    wrapMode: Text.WordWrap
-                    color: panel.theme.textSoft
-                    font.family: panel.uiFont
-                    font.pixelSize: 8
-                }
             }
 
             Item { Layout.minimumHeight: 8 }
diff --git a/apps/arstack_studio/qml/SignalMatrix.qml b/apps/arstack_studio/qml/SignalMatrix.qml
index f00843460..5d23c3b76 100644
--- a/apps/arstack_studio/qml/SignalMatrix.qml
+++ b/apps/arstack_studio/qml/SignalMatrix.qml
@@ -204,6 +204,20 @@ Rectangle {
                         suffixText: matrix.groupIndex === 0 ? "A" : "V"
                         text: signalRow.mag.toFixed(3)
                         invalidInput: false
+                        TapHandler {
+                            acceptedButtons: Qt.RightButton
+                            onTapped: {
+                                if (signalRow.rowIndex < 3) magnitudeMenu.popup()
+                            }
+                        }
+                        SignalQuickMenu {
+                            id: magnitudeMenu
+                            theme: matrix.theme
+                            controller: matrix.controller
+                            groupIndex: matrix.groupIndex
+                            rowIndex: signalRow.rowIndex
+                            phaseMode: false
+                        }
                         onActiveFocusChanged: {
                             if (activeFocus) {
                                 matrix.controller.selectSignal(matrix.groupIndex, signalRow.rowIndex)
@@ -254,6 +268,20 @@ Rectangle {
                         suffixText: "°"
                         text: signalRow.angle.toFixed(2)
                         invalidInput: false
+                        TapHandler {
+                            acceptedButtons: Qt.RightButton
+                            onTapped: {
+                                if (signalRow.rowIndex < 3) phaseMenu.popup()
+                            }
+                        }
+                        SignalQuickMenu {
+                            id: phaseMenu
+                            theme: matrix.theme
+                            controller: matrix.controller
+                            groupIndex: matrix.groupIndex
+                            rowIndex: signalRow.rowIndex
+                            phaseMode: true
+                        }
                         onActiveFocusChanged: {
                             if (activeFocus) {
                                 matrix.controller.selectSignal(matrix.groupIndex, signalRow.rowIndex)
diff --git a/apps/arstack_studio/qml/SignalQuickMenu.qml b/apps/arstack_studio/qml/SignalQuickMenu.qml
new file mode 100644
index 000000000..27724359c
--- /dev/null
+++ b/apps/arstack_studio/qml/SignalQuickMenu.qml
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+import QtQuick
+import QtQuick.Controls
+
+Menu {
+    id: quick
+    property var theme
+    property var controller
+    property int groupIndex: 0
+    property int rowIndex: 0
+    property bool phaseMode: false
+    width: 238
+    padding: 5
+    background: Rectangle { radius: 8; color: quick.theme.raised; border.width: 1; border.color: quick.theme.line }
+    // Inline menu items share the same explicit dark presentation, including
+    // declarative MenuItem children (Menu.delegate only styles Actions).
+    component QuickAction: MenuItem {
+        id: action
+        implicitWidth: quick.width - 10
+        implicitHeight: 34
+        contentItem: Text {
+            text: action.text
+            color: quick.theme.text
+            font.pixelSize: 11
+            verticalAlignment: Text.AlignVCenter
+            leftPadding: 10
+        }
+        background: Rectangle { radius: 6; color: action.highlighted ? quick.theme.accentSoft : "transparent" }
+    }
+    QuickAction {
+        text: quick.phaseMode ? "Equal Angle · A B C" : "Equal Value · A B C"
+        onTriggered: quick.controller.quickSetGroup(quick.groupIndex, quick.rowIndex,
+                                                     quick.phaseMode ? "equal_angle" : "equal_value")
+    }
+    QuickAction {
+        visible: quick.phaseMode
+        height: visible ? implicitHeight : 0
+        text: "Balance ABC · 120°"
+        onTriggered: quick.controller.quickSetGroup(quick.groupIndex, quick.rowIndex, "balance_angle")
+    }
+}
diff --git a/apps/arstack_studio/qml/WaveformExpertPanel.qml b/apps/arstack_studio/qml/WaveformExpertPanel.qml
index fdc888d96..cb9805cda 100644
--- a/apps/arstack_studio/qml/WaveformExpertPanel.qml
+++ b/apps/arstack_studio/qml/WaveformExpertPanel.qml
@@ -35,7 +35,7 @@ SurfacePanel {
             RowLayout {
                 anchors.fill: parent
                 anchors.margins: 12
-                CheckBox { id: enabledCheck; checked: panel.controller.ctSaturationEnabled; text: "Enable CT saturation stress"; font.family: panel.uiFont; font.pixelSize: 10 }
+                DarkCheckBox { id: enabledCheck; theme: panel.theme; checked: panel.controller.ctSaturationEnabled; text: "Enable CT saturation stress"; font.family: panel.uiFont; font.pixelSize: 10 }
                 Item { Layout.fillWidth: true }
                 Label { text: panel.controller.ctSaturationEnabled ? "ACTIVE" : "CLEAN SINE"; color: panel.controller.ctSaturationEnabled ? panel.theme.amber : panel.theme.muted; font.family: panel.uiFont; font.pixelSize: 8; font.weight: Font.Bold }
             }
diff --git a/apps/arstack_studio/src/DeterministicSessionHarness.cpp b/apps/arstack_studio/src/DeterministicSessionHarness.cpp
index 55e1e90da..d3de5981e 100644
--- a/apps/arstack_studio/src/DeterministicSessionHarness.cpp
+++ b/apps/arstack_studio/src/DeterministicSessionHarness.cpp
@@ -42,6 +42,7 @@ class DeterministicSessionHarness final {
             {"manual recovery intent survives IDENTIFY -> firmware required", manualRecoveryIntentArmsFirmwareOffer()},
             {"stale generation release -> ignored", staleReleaseGenerationIsIgnored()},
             {"firmware probe before serial release -> blocked", firmwareProbeRequiresReleasedPort()},
+            {"ABC preparation rejects partial or out-of-range batches", abcSetBatchIsAllOrNothing()},
             {"PTP staged START requires role/config/runtime ACKs", ptpGuidedStartNeedsAcks()},
             {"PTP stale role readback cannot bypass ACK", ptpStaleRoleReadbackBlocked()},
             {"PTP runtime requires matching PTP2 role", ptpRuntimeRoleEvidenceRequired()},
@@ -343,6 +344,37 @@ class DeterministicSessionHarness final {
             session.diagnosticsText().contains(evidence);
     }
 
+    static bool abcSetBatchIsAllOrNothing() {
+        const auto sample = [](const QString& id, const double magnitude,
+                               const double phase, const qulonglong quality) {
+            return QVariantMap{
+                {QStringLiteral("signalId"), id},
+                {QStringLiteral("magnitude"), magnitude},
+                {QStringLiteral("phase"), phase},
+                {QStringLiteral("quality"), quality}};
+        };
+        QVariantList values{
+            sample(QStringLiteral("Ia"), 1.0, 0.0, 0),
+            sample(QStringLiteral("Ib"), 1.0, -120.0, 0),
+            sample(QStringLiteral("Ic"), 1.0, 120.0, 0)};
+        const QStringList commands =
+            DeviceController::buildThreePhaseSetBatch(values, 1000, 100, 50.0);
+        if (commands.size() != 3 ||
+            commands[0] != QStringLiteral("SET IA 1000 0 0") ||
+            commands[1] != QStringLiteral("SET IB 1000 -120000 0") ||
+            commands[2] != QStringLiteral("SET IC 1000 120000 0")) return false;
+
+        values[1] = sample(QStringLiteral("Ia"), 1.0, -120.0, 0);
+        if (!DeviceController::buildThreePhaseSetBatch(values, 1000, 100, 50.0).isEmpty())
+            return false;
+        values[1] = sample(QStringLiteral("Ib"), 1.0e12, -120.0, 0);
+        if (!DeviceController::buildThreePhaseSetBatch(values, 1000, 100, 50.0).isEmpty())
+            return false;
+        values[1] = sample(QStringLiteral("Ib"), 1.0, -120.0, 0);
+        values.removeLast();
+        return DeviceController::buildThreePhaseSetBatch(values, 1000, 100, 50.0).isEmpty();
+    }
+
     static bool optionalBootloaderWaitCanCancel() {
         Fixture fixture;
         if (!fixture.profileReady) return false;
diff --git a/apps/arstack_studio/src/DeviceController.cpp b/apps/arstack_studio/src/DeviceController.cpp
index bbb1bb5e7..c1936c4ca 100644
--- a/apps/arstack_studio/src/DeviceController.cpp
+++ b/apps/arstack_studio/src/DeviceController.cpp
@@ -679,6 +679,73 @@ bool DeviceController::setSignal(
         .arg(static_cast<qulonglong>(quality)));
 }
 
+QStringList DeviceController::buildThreePhaseSetBatch(
+    const QVariantList& setpoints,
+    const double currentCountsPerAmp,
+    const double voltageCountsPerVolt,
+    const double frequencyHz) {
+    if (setpoints.size() != 3 || !finitePositive(currentCountsPerAmp) ||
+        !finitePositive(voltageCountsPerVolt)) return {};
+
+    const QString first = setpoints[0].toMap().value(QStringLiteral("signalId"))
+                              .toString().trimmed().toUpper();
+    const bool currents = first == QStringLiteral("IA");
+    if (!currents && first != QStringLiteral("UA")) return {};
+    const QStringList expected = currents
+        ? QStringList{QStringLiteral("IA"), QStringLiteral("IB"), QStringLiteral("IC")}
+        : QStringList{QStringLiteral("UA"), QStringLiteral("UB"), QStringLiteral("UC")};
+    const double scale = currents ? currentCountsPerAmp : voltageCountsPerVolt;
+
+    QStringList commands;
+    commands.reserve(3);
+    for (int i = 0; i < 3; ++i) {
+        const QVariantMap item = setpoints[i].toMap();
+        if (item.value(QStringLiteral("signalId")).toString().trimmed().toUpper() != expected[i])
+            return {};
+        bool magnitudeValid = false;
+        bool phaseValid = false;
+        bool qualityValid = false;
+        const double magnitude = item.value(QStringLiteral("magnitude")).toDouble(&magnitudeValid);
+        const double phase = item.value(QStringLiteral("phase")).toDouble(&phaseValid);
+        const quint64 quality = item.value(QStringLiteral("quality")).toULongLong(&qualityValid);
+        if (!magnitudeValid || !phaseValid || !qualityValid ||
+            quality > std::numeric_limits<quint32>::max() ||
+            !std::isfinite(magnitude) || !std::isfinite(phase) ||
+            (frequencyHz > 0.0 && magnitude < 0.0)) return {};
+
+        const double scaled = magnitude * scale;
+        const double angleMilli = phase * 1000.0;
+        if (!std::isfinite(scaled) || !std::isfinite(angleMilli) ||
+            scaled < std::numeric_limits<qint32>::min() ||
+            scaled > std::numeric_limits<qint32>::max() ||
+            angleMilli < std::numeric_limits<qint32>::min() ||
+            angleMilli > std::numeric_limits<qint32>::max()) return {};
+        const auto counts = std::llround(scaled);
+        const auto phaseMdeg = std::llround(angleMilli);
+        commands.append(QStringLiteral("SET %1 %2 %3 %4")
+            .arg(expected[i])
+            .arg(counts)
+            .arg(phaseMdeg)
+            .arg(quality));
+    }
+    return commands;
+}
+
+bool DeviceController::setSignalsBatch(
+    const QVariantList& setpoints,
+    const double currentCountsPerAmp,
+    const double voltageCountsPerVolt) {
+    const QStringList commands = buildThreePhaseSetBatch(
+        setpoints, currentCountsPerAmp, voltageCountsPerVolt, signalFrequencyHz_);
+    if (commands.size() != 3) {
+        setError(QStringLiteral("ABC batch is invalid; no phase was queued."));
+        return false;
+    }
+    // Exactly one queued worker call. DeviceIoWorker checks ALL THREE slots
+    // before enqueueing ANY; a full queue cannot accept an ABC prefix.
+    return sendCommandBatch(commands, false);
+}
+
 bool DeviceController::setEnabled(const QString& signalId, const bool enabled) {
     return sendCommand(QStringLiteral("ENABLE %1 %2")
         .arg(signalId.trimmed().toUpper())
diff --git a/apps/arstack_studio/src/DeviceController.hpp b/apps/arstack_studio/src/DeviceController.hpp
index f77ebf2c3..8518403c6 100644
--- a/apps/arstack_studio/src/DeviceController.hpp
+++ b/apps/arstack_studio/src/DeviceController.hpp
@@ -7,6 +7,7 @@
 #include <QThread>
 #include <QTimer>
 #include <QVariantMap>
+#include <QVariant>
 
 class DeterministicSessionHarness;
 class DeviceIoWorker;
@@ -221,6 +222,8 @@ class DeviceController : public QObject {
         quint32 quality,
         double currentCountsPerAmp,
         double voltageCountsPerVolt);
+    // One all-or-none worker queue submission for fast ABC operator actions.
+    bool setSignalsBatch(const QVariantList& setpoints, double currentCountsPerAmp, double voltageCountsPerVolt);
     bool setEnabled(const QString& signalId, bool enabled);
     bool setQuality(const QString& signalId, quint32 quality);
     bool setCtSaturation(bool enabled, double dcOffsetPercent, double harmonicPercent, int harmonicOrder, double clipPercent);
@@ -351,6 +354,9 @@ class DeviceController : public QObject {
     bool beginPtpStopVerification();
     void markPtpStopUnconfirmed(const QString& reason);
     void resetPtpStartup() noexcept;
+    [[nodiscard]] static QStringList buildThreePhaseSetBatch(
+        const QVariantList& setpoints, double currentCountsPerAmp,
+        double voltageCountsPerVolt, double frequencyHz);
     [[nodiscard]] static QString ptpConfigCommand(const QVariantMap& profile);
     static QString cleanLine(const QString& rawLine);
     static QString utf8Hex(const QString& text);
diff --git a/apps/arstack_studio/src/SmartSessionController.cpp b/apps/arstack_studio/src/SmartSessionController.cpp
index 8c052266e..e75c0d628 100644
--- a/apps/arstack_studio/src/SmartSessionController.cpp
+++ b/apps/arstack_studio/src/SmartSessionController.cpp
@@ -385,6 +385,14 @@ bool SmartSessionController::requestSetSignal(
             voltageCountsPerVolt);
 }
 
+bool SmartSessionController::requestSetSignalsBatch(
+    const QVariantList& setpoints,
+    const double currentCountsPerAmp,
+    const double voltageCountsPerVolt) {
+    return liveControlReady() && device_ != nullptr &&
+           device_->setSignalsBatch(setpoints, currentCountsPerAmp, voltageCountsPerVolt);
+}
+
 bool SmartSessionController::requestSetQuality(const QString& signalId, const quint32 quality) {
     return liveControlReady() && device_ != nullptr && device_->setQuality(signalId, quality);
 }
diff --git a/apps/arstack_studio/src/SmartSessionController.hpp b/apps/arstack_studio/src/SmartSessionController.hpp
index b31d2a673..6476ef8f3 100644
--- a/apps/arstack_studio/src/SmartSessionController.hpp
+++ b/apps/arstack_studio/src/SmartSessionController.hpp
@@ -179,6 +179,11 @@ class SmartSessionController : public QObject {
         quint32 quality,
         double currentCountsPerAmp,
         double voltageCountsPerVolt);
+    // One all-or-none worker FIFO admission for fast ABC operator actions.
+    Q_INVOKABLE bool requestSetSignalsBatch(
+        const QVariantList& setpoints,
+        double currentCountsPerAmp,
+        double voltageCountsPerVolt);
     Q_INVOKABLE bool requestSetEnabled(const QString& signalId, const bool enabled) {
         return liveControlReady() && device_ != nullptr && device_->setEnabled(signalId, enabled);
     }
diff --git a/apps/arstack_studio/src/StudioIcon.rc b/apps/arstack_studio/src/StudioIcon.rc
new file mode 100644
index 000000000..545c46c57
--- /dev/null
+++ b/apps/arstack_studio/src/StudioIcon.rc
@@ -0,0 +1,2 @@
+// Use the dedicated Studio icon. Workbench/favicon resources stay untouched.
+1 ICON "../../../assets/studio_icon/favicon.ico"
diff --git a/apps/arstack_studio/src/main.cpp b/apps/arstack_studio/src/main.cpp
index f208cd705..6f7ee1513 100644
--- a/apps/arstack_studio/src/main.cpp
+++ b/apps/arstack_studio/src/main.cpp
@@ -20,6 +20,7 @@
 #include <QPointer>
 #include <QQmlApplicationEngine>
 #include <QQuickWindow>
+#include <QIcon>
 #include <QThread>
 #include <QTimer>
 #include <QtQml/qqml.h>
@@ -438,6 +439,7 @@ int main(int argc, char* argv[]) {
 
     QGuiApplication app(argc, argv);
     app.setQuitOnLastWindowClosed(true);
+    app.setWindowIcon(QIcon(QStringLiteral(":/studio/favicon.ico")));
     QCoreApplication::setOrganizationName(QStringLiteral("ARStack61850"));
 #ifdef ARSTACK_STUDIO_ENGINEERING_PREVIEW
     QCoreApplication::setApplicationName(QStringLiteral("ARStack Studio Preview"));