Adding version back into stripped UnityFS header?

[monlupin]

I have some UnityFS files that have had the version stripped from the headers, and I want to add it back in. I've tried changing the version to the correct one -> finding the new file size -> updating the archive size but it doesn't work. Am I missing something? Doing it completely wrong?


Example header, highlighted is what I'm editing for archive size (original file size is 2,573,768/2745C8 bytes). Here's the file.

For a bit more background if need be, it's a mobile game called Yumekuro (ゆめくろ), these are character sprites that have been diced, and AssetStudio errors if you try to do anything with the undiced versions. I've gotten it to load undiced sprites on the same version of Unity (2020.3.21f1) in a test game, so I think it's just missing some file, but I can't troubleshoot it because no other program will load it with its version stripped. Any advice is appreciated!