Nice concept, graphics are great, sound decent, but the controls were horrific. Many times unresponsive, I constantly found myself having to reset the game because the player would no longer jump. Not sure what you were using to prevent double jumping, but it made for a frustrating time when you were on a crate or fan edge and could not jump or move. At least there was a reset level button. Also, it would have been nice to know which object was in which slot as switching between moving/jumping and selecting objects for the other control often led to deselecting the wrong object which also got me stuck and resetting the level several times. Maybe you could color one with a blue outline and the other with a red outline. Also, maybe have an X and a Y on the outline for those that are color blind. While the separate mouse and keyboard controls are a little different to get used to, they could work well for a puzzle game like this if they were just a tad more responsive. One other issue I could not figure out was why sometimes the jump would literally just be a tiny hop, not even enough to get on the small crates and other times a jump would be just shy of getting on the large crates. I get that it was designed as a momentum game, so I'm guessing you are using forces, but for some reason the forces aren't being applied correctly?? Finally, the glass feature was fun, but many times the glass would not break no matter how big the crate on it was. I'm pretty sure that is just a collision box detection bug. Would love to see more objects and more levels once the bugs are worked out of the game!
Some suggested edits:
Color code (text code for color blind) the selected objects.
Instead of physics based, use speed/position based movement and condition checks for more nuanced controls.
Instead of pushing objects, allow the player to hold small/medium crates with hold/throw button.
For the glass objects, increase the size of the collider.