Are you using you're own copy or or from a RomSet? The copy I was using was from ReDump on the MegaSg. I know the original works fine on original hardware because I had bought this game new many years ago and played it on my Genesis model 1 with Sega Cd model 1. I am also using the current released firmware (MegaSD_firmware_1.02_R04). Are you using one of the beta/tester builds? I tried with MegaCD bios 2.0 and 2.00 but didn't try with other BIOS, which BIOS rev were you using?