Woah
I'm genuinely amazed. You managed to stick to the bare bone gameplay mechanics of a platformer, and yet messed with the concept more than any other platformer i've ever played. I was impressed when the screen first rotated & gravity changed, but i assumed it was probably just a neat little trick that would be used infrequently and was probably painstakingly scripted each time... well yeah, i was just a bit wrong.
Later on in the game i honestly had no idea what was going on, but in a GOOD, liberating way. Despite occasionally completely losing track of where i was, the levels were still designed so well that still i always blundered into the exit without having to backtrack.
The 'boss battles', if you can even call them that, were also ingenius. Completely random and not really explained, but presented in such a way that you knew what to do anyway. I also loved how the game got progressively darker as it when on, and i'm always a sucker for psychiatric issues, so the highly depressing ending only made me smile =]
As per usual, i spent most of the time playing trying to work out how the engine probably worked, and i eventually came up with the idea that maybe crossing certain tiles on a grid triggers everything to flip around... that's the only way i can think of doing it that wouldn't make designing each level obscenely frustrating, and i'm still not convinced that that's it x.x
The only criticism i would have of this game is probably the reason for its brutally unfair score... it starts a little bit slow. The true complexity of the game doesn't really show itself until after the first few levels, and the only reason i kept on playing myself was because i gave it the benefit of the doubt out of boredom. My guess is that a lot of people are just closing the window after the first couple of levels, which is a huge shame =/
I would personally place this somewhere in the top 50, but hey, maybe that's just me =]