Lemmings 2 works now but vertical scrolling is jerky.
I was looking at this today and found that UNZ does the same if the "CPU fullspeed" option is set. I'm not sure what it means though.
Edit: Seems like a bug in the game. It flips the buffers after writing to the crtc regs then draws the frame after next to the back buffer, which is still being displayed until the next vblank. I can't find any videos on the internet of this so I don't know how it looks on real hardware.
