Well, since the last update, I hooked up most/all of the Star Rider inputs and then tried inserting two coins to see how well a game would play. At this point, the game locked up. I started debugging/disassembling to find out what why, and as far as I can tell, the game has either entered an error state and locked up intentionally, or... I am not sure. It is basically looping/waiting for VBLANK to start but every time VBLANK starts, the interrupt service routine starts, preventing the non-interrupt loop from ever ending.
Disassembling the main CPU is much harder than the PIF CPU because it has a lot more RAM (and uses a lot more of it), and has a lot more code.