Micro Machines and Ultimate Stuntman both have big problems with the racetrack getting corrupted on the Everdrive N8. Could be a problem with Camerica mapper 71 maybe?
Some pictures here:http://forums.nesdev.com/viewtopic.php?p=188856#p188856
Edit: as a test I changed the Ultimate Stuntman header to use mapper 2 (it seems UNROM compatible), and it appears to work correctly with that header change, so I suspect the mapper 71 implementation is the problem?
Edit 2: Seems like both games write $00 to $8000-BFFF at startup, and the mapper implementation must get confused by this, presuming it has mapper-controlled single screen mirroring instead of the fixed mirroring both of these games have. Only Fire Hawk should have single screen mirroring.
FCEUX seems to work around this by limiting the mirroring register to $9000-9FFF? (source
) Apparently Fire Hawk only writes it as $9000, and the rest of the games that don't have mirroring control write it at $8000?