Game runs now fine! I was a bit annoyed at the postage stamp size screen, but Alt-Enter to fullscreen mode worked, so that's not a biggie. Awesome sound and graphics and a great idea! I got stuck at level where there is more level to be seen on the mirror side player, but I couldn't figure out how to either a) change the camera to the mirror player, or b) figure out the correct movement patternt without seeing the mirror player. Maybe the 3rd item would help with that? The black dot? However, I couldn't activate it so maybe I'm not understanding the game mechanics correctly.
A solid submission nevertheless, good work!