The game is really good, I enjoyed it a lot! The only thing I have to say is that the controls are a bit frustrating, especially because of the the very short timer. For example:
- the jump when you hit the ceiling
- the fact that you cannot place a block where you are
- the fact that you cannot place a block up or down (i understand this from a level design point of view, but maybe it only needs to be clear (like drawing the allowed places lightly))