Well, it doesn't seem to write or read from 0x50000-FF, I just ran it with the debugger and a save state. Must be something else going on, perhaps an internal checksum is triggered or other rom protection measure :/You can probably do a lot of debugging in MAME by setting appropriate watchpoints and using cheats.Even if MAME doesn't crash at least you'll have locations writing to the ARM.Opcode 1010, no idea what that is.I need to debug (credit feed?) this and find out if it's a sneaky trigger they have in stage 4. The code at 0x14169E might contain a write/check for something.
Note this wasn't extensively tested, and i'm not skilled enough to reach second loop on White Label or even Black Label.
If they have some tests/protection trick when the true boss Hibachi shows up and it crashes then & there, that's gonna be an issue