As Racinak pointd there's something weird in level 4 but it's totally finishable if anyone wonder (but dunno how many level because I didn't count ^^').
The simple princple of rotating the level and finishing it, played it and finished in something like 5 mins, was fun and calm. Not too much rotating making me wanting to close the windows, needs a bit of polish and things like that but the game works and is pleasant.
Well done (and yeah, get some sleep :p!).