We just wanted to inform everyone that apparently the PC version of the demo isn't actually the demo. It is an unfinished version of the game with many things left undone, some of the levels don't work at all. We are working on trying to figure out why this has happened. A decent amount of the game does work, so you can still download it and try it if you want, but its more like a beta test than an actual demo.
People using a mac should be fine. As far as we can tell the mac version is the actual demo. Again we are working on fixing this as fast as we can. Thank you for your understanding.