[Solved] Unpacking .cat File from PSVita Game

[functionRand]

Hello Everyone!
First-Time Poster here!

I'm trying to unpack a .cat file from a PSVita Game. I already tried the neptunia_pp.bms & neptunia_rebirth1.bms Scripts I found here but they don't seem to work.
While the neptunia_rebirth1.bms Script doesn't work at all with my file, the neptunia_pp.bms Script somewhat can unpack the file but I'm sure something isn't correct because just repacking the unmodified file(s) just errors out.

I already tried many things and reading into bms' scripts but I simply can't get it to work. But I don't want to give up this Project, so I'm asking if someone could help with a Script?
The File I'm trying to modify is attached (packed in .zip Archive).

Thank you all and I'm really glad I found this Forum!
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Edit: I've made a tool, which can do what I need. As of now, no help is needed for this file anymore.