Interesting thanks for looking, same exact behavior with Takeda's emulator so I wonder if his dumping process (he uses the actual machine to dump the carts) is creating the dumps with A13 inverted and this lead to the wrong implementation on the emulators?
The existing BASIC cart dump does work in both emulators, so if that's true that dump would need to be fixed I guess?

The video output in MAME has lots of issues btw, hopefully this can be fixed now that we have one dump available. The game is also incredibly sluggish, but I think that's just how bad it is smile