I'm getting perpetual resets in the last battle of Final Fantasy IV at both 156 and 166 MHz (my GP32 runs SNES9xGP at 172 MHz stably), and have tried flipping stuff in the debug options, disabling sound, everything.
Also that 4-way screen splitting bug is present (Rockman X and Aero Fighters have done it within 5 minutes of gameplay), but simply entering and exiting the Select menu fixes it.