thanks for the info it was helpful, now i understand what's going on here but i don't see me getting this to work.. along with CRCs i also need SHA1 codes, memory address locations, rom regions, and a bunch of stuff. i tried just changing the names of the files and CRCs from the driver for the encrypted version but ofcourse that didn't work. also there are some files that are different filenames. i suppose my best bet is finding the encrypted romsets for which i have the drivers.. but i've looked everywhere already =/ i guess i can try getting gngeo to play them...