.add file extension

[KingVariares]

Does anyone think they can help me decode/decrypt the .add files in this .iso I want to do a rom hack on. .add files are a composition of .vag, .gmo, or .gim files. I am able to extract the files by going through it with a hex editor and erasing the data between each file and then going back and extracting them each time one by one. This works fine for extraction but the issue I have is recompiling the .add file. I try to make an .rar and rename the extension to .add, but the game ignored the file when I patched it into the rom. (it was an audio .add) there were no voice lines for that character.