Brilliant
Concept: 9/10-
even though the idea was from another game, it was still brilliantly executed
Graphics: 8/10
pretty darn good graphics considering how little lag there was
Physics: 10/10
I haven't seen this good of physics in a while, awesome action scripting.
Overall: 10/10
I love this game, lvl 37. I can't wait till I beat it. I'm disappointed that there are only 40 levels, but I understand how hard it must have been for you to have made 40. If you ever do get a chance, I'd advise you to make a sequel. I think this should be an advertisement for the official Valve game. I might even go out and get the real game now that I've seen how awesome this is.
Kudos
-PB