You can pick up some coins, but not other ones. I can pick up blue potions, but not red ones. Why?
You should include a fullscreen option. More music would be helpful.

I tried this. Only got as far as the instructions screen, which is very nice graphics, btw, very textured and slick. But no amount of wasd, space, O, or anything else got me from there to the start screen; simply stuck on instructions page. I think this needs more work, but I will come back to it later to see if you've figured out why it is hanging like this.