I was going to blurt out LOCK-ON but holy cow, it's fully working now! I feel smart.
I'm gonna be busy later playing that... But if I were so bold to go on...
Marble Madness 2 - yeah, it's probably ready to go if only the roms were to be dumped. This will never happen. And I'm not flying out to San Diego just to play it at CAX. Nothing can be done, just a sad situation that may never change. I hope the idiot owner has backed up the roms, at least.
Air Combat (not working) - No port exists, the PSX game that has this name is not the arcade game. I may be building an upright from gathered parts, long term project.
Daioh (working) - Audio imperfection during gameplay, a sound effect keeps repeating that should not be there. (I used to own the machine years ago, loved it)