Actually, I used a binaries-based installation. You said you had to transfer the bios and the roms from mame to gngeo? I have duplicate copies in each directory. Did you load the bios by trying to run it as a game, then launch a different game in gngeo?
Thanks for the help. I really appreciate it. I’m trying to get everything ready for a full arcade cabinet build. I’m just about to start construction, actually. If anyone else has any insight into this problem, I could really use it!