Very cute! I sat through and quite enjoyed the entire game and I've think you've done extremely well making this game!
Good things:
Lots of small things that help bring together is the variety of music that makes the game rather pleasant and enjoyable especially with the different areas and resulting color palette.
Great sound design that gives player feedback at every play input. Great visual feedback to let the player know what blocks the magnets are attached to. Overall, lots of good small things that bring the thing together!
Caveats:
The puzzles sometimes feel easy and sometimes feel extremely difficult. The pacing is a bit off as a result which is probably a result of a lack of varied mechanics.
To be fair, I also can't really criticise from that basis simply because you were developing on a time constraint. Although may I suggest, that should you continue developing the game, that you can consider adding more mechanics, or different sized/shaped rooms to better pace the difficulty?
Great game~