There are a lot of really hard platformers out there, but this isn't one of them. It's actually kind of refreshing to see a platformer that's this easy. There's very little frustration. The controls are good. The levels are short and simple.
The achievement lied to me when it said "Congratulations, you died A LOT!" I didn't die at all on that level, and it said it was the hardest level in the game. I thought level 8 was the hardest, and that was only because of timing the jumps in the first half of it. But now I'm looking back, and it looks like there's a glitch that makes the level go straight from 9 to 11. I never played level 10. You should put a level indicator in there that shows what level you're on to avoid these bugs in the future. Also, the mute/back buttons seem to be missing in level 11.
Why is it called death count? Because there is no death count? Because you're expected to die a lot? It's kind of ironic that a platformer which boasts about a high difficulty level would be so much easier than average.
I'm a little peeved that you're calling this a puzzle platformer though. So many games call themselves that when they're not! Time Fcuk, Chronotron, The Company of Myself, Fixation, any of the Portal games made in Flash, these are puzzle platformers because they're about solving puzzles. Your game is mostly skill-based, being about precision and timing.