Been taking a small break from looking into it so no real progress. Just some small info of where the first few times it tries to load the graphics data. Which seems to be in the 3rd hidden script (bloody huge script... friggin 1.9k lines) on the third animation name. The hidden animation scripts I think first get called in one of the standard scripts about half way through the list of scripts (idk script name as it's some Japanese name pretty sure, think it has "8_dir_movement" in it tho or smth similar).Have you tried bypassing the check by just packing it into an rgss3a after you finished your modifications?
Also, I would interested in decrypting it. Always neat to see what can be changed in a game.
However already tried that and doesnt work sadly. Think Im going to look into it a bit more at some point then and if nothing try looking into how the patching system works. Tho the patch files are probably done by an in house program which would make things interesting.