That was a lot of fun! I liked the puzzles and the overall feel of the game. Obviously things like sound and music would improve the experience but this was fine for a warmup :)
The only suggestion is you could make the breakable floors more distinct. Noticing them isn't really part of the puzzles and only serve to frustrate the player. I tend to think that puzzle games should have all the elements easy to display at the start. But if that's not what you were going for just ignore me :)