Hi, to decompress PlyLevelTbl.cpt you first need to shave off its header, for instance with a hex editor like ImHex. (The header is "00 00 71 00 F3 5D 62 CE")
Then with fuzziqersoftware's
newserv run the following commands (modify input / output filenames and paths accordingly):
Code:
newserv decrypt-data --pc --big-endian --seed=F35D62CE file.cpt file.decrypted
Code:
newserv decompress-prs --big-endian file.decrypted file.decrypted.decompressed
Then your only option to modify the file I guess is to use a hex editor after reading up on info about the file structure and offsets.
I suppose it's possible to recompress and then reencrypt a modified file, but I have never done so because I recently started making a graphical user interface / application to edit PlyLevelTbl.cpt using code by fuzziqer (small parts of Phosg and Newserv). I don't plan on releasing the app because I'm not confident in the safety and performance of my code.