Repacking FPS4 Files for Tales of the Abyss on 3DS

[ZCY-cyber]

I’ve been working on unpacking the files for Tales of the Abyss on the 3DS platform and found that the text data is stored within FPS4 files. I used a specific project to extract these files, and while the extraction itself seems successful, I encountered an issue when trying to repack them—the resulting file structure appears to be incorrect and is not recognized by the game. I’ve attached some sample files for reference. I was wondering if there might be a working repacking tool available, or if anyone could offer guidance on resolving this. Any help would be greatly appreciated. Thanks!
FS4.zip

[AdmiralCurtiss]

FPS4 is a stupid format that has a million different variants and exceptions so this is not too surprising. In fact it even recognizes that it's an unsupported type:

WARNING: Content Bitmask (0x001B) identifies unknown data types, data interpretation will probably be incorrect.

But yeah this is probably handleable...

[AdmiralCurtiss]

They don't roundtrip bitexact but does this fix the issue? Make sure you use the -j feature on extraction and repack with that json file.

[ZCY-cyber]

Thank you for the previous help! I have been using the -o parameter in ToVfps4p while preserving the original file headers and JSON files. After testing, the game seems to run normally. Next, I plan to test cases where Japanese characters exceed typical length limits—for example, using five Japanese characters versus six English characters—and attempt to increase the length of the .sb7 file. I will check whether the offsets within the file are calculated correctly under these conditions.
I am currently unsure whether the project is calculating text pointers correctly during the repacking process.