Cool idea
I enjoy abstract games like this. It's a very good concept and well executed.
I basically have three beefs with this game:
1) No sound.
2) I wish that there was a way to complete the stage (either an exit or something to collect -3 gems for instance). I know that objective completion isn't the point of the submission, but it's still nice to be able to finish a stage.
3) There is still a problem with people screwing around with perfectly good levels. Thrice in one minute I've had someone (presumably) purposely box me into a spot so that I have to leave the stage. I understand that you can't stop people from being dicks, but it would be nice if there were ways for players to get around this (maybe a button to force a teleport?).