I've tried several games. The problem I'm having at this point is that every time opcode 42 comes up, the emulation freezes. It renders one frame of op 42 and then stops completely. I'm trying to find out why it does that and what I need to change; it seems like the emulator's waiting for op42 to do something, but I don't know what or why. (This being the first time I've ever worked on an emulator of any kind at all, I'm trying my best to trace through all the code and find the source of this problem, but I'm not entirely certain where to even look, so it's taking a while.)
I've looked at the source code of several emulators that implement speedhacks - SNESAdvance, snes9x_tyl, SNEmulDS, and others - but without knowing where to look to begin with (looking at the actual op42 function didn't help), they're not proving to be very useful.