Impressive.
This is much more than meets the eye. It reminds me of "Bouncy the Ball". I loved the level design, and I loved the artwork in the background. It would probably run smoother if you used the virtual camera. That would make the script to make the background move slower oh so slightly more complicated, though. Actually, come to think of it, all you would have to do is reverse the _x speed, not alter the speed itself.
The controls were glitchy at times, but overall pretty good.
The script for a platformer is MUCH more complicated than it looks (I know, I've tried...and failed...many times), so I applaud the game's concept even.
I was very impressed with this. Great job!