Clever mechanic! The puzzle design is very good. The tutorial lets you think for yourself a little bit, which is nice.
Movement was a bit unpleasant though, the ball was too slow in acceleration and deceleration, and was hard to control in the air (very slow without momentum).
There was also a bug that disabled your jumping. I encountered this several times in the "show me what you've learned" level. It seemed to happen when I fell on a button and a floor at the same time.
I encountered this bug once more in the next level, and in that one the restart button didn't work, so it ended the game for me.
The puzzles and levels were great though!