I think this is one of, if not my favorite game in the jam. What a crazy concept. I never thought I'd say this, but this game reminds me a lot of quantum mechanics lol
The atmosphere is superb, I love how the music tracks just build upon the track of the previous level, and the concept is amazing. I think level 3 was too hard - it should have been the last or second-to-last level, as a lot of people didn't make it through. I almost gave up too, and it's a shame because the solution is not complex once you find out the answer.
I enjoyed how the cube added a new object that you need to take care not to leave your field of view. But I think the concept could be explored more - only in the last level does the cube concept shine. And I also thought that it was too hard to get the cube to the top of the button - it always gets stuck.
If you press "Shift" you sprint, which is a good option as the default speed is too slow. But this sprint is so much faster than the regular speed that it looks like a debug option you forgot to remove. My recomendation (you decide if you want to follow it) is to make the default walk speed faster than the current speed (like 2x as fast), keep the sprint, but make it slower than what it is now.
Overall, I gave it 5 stars in every category, a first for this jam. Well done, you deserved it!