Physics engine keeps usurping my play. You shouldn't be able to jump up through it, nor should it be able to fly through any line when it's going fast enough.
A good game - but getting the achievement may drive you insane. I've just spent at least an hour trying to complete the last Ace level.
But the sense of achievement is so worth it.
The physics engine is a little buggy - sometimes if you hit the side of a wall, it will teleport you above it, underneath it, or even to the opposite end of it. Rewrite it to use Box2d and I'll give you 5 stars for sure :)
It's a very good concept - but I think the timing puzzles ruin it. More logic puzzles would have been brilliant, but instead I found myself repeatedly dying on "Fred Astaire-case" on Uneasy difficulty.