Complaints:
1) Bugs were everywhere, and at time, it made the game borderline unplayable. I think the other comments have already addressed the ones I found though, so I'm not gong to elaborate too much.
2) The sound effect when a ball hit the finish really bothered me. I would suggest either making it way quieter or just replacing it with a different sound.
Compliments:
1) The actual gameplay was quite good, and I liked the level design from the ones I saw. The puzzle were pretty fun.
2) The take on the theme was cool, with the different routes you could take.