That's a really well mastered level design you got there, I loved it! Did you made other games before this one? This really doesn't seem to be your first one, or you're very talented.
Some people said the screen rotation was introduced too early but I think it was perfect this way : I spent a the third of the game thinking it was an useless mechanic until it became necessary and I suddenly felt so proud when I figured it out after being blocked. Didn't think the storytelling could help teasing an important mechanic, that was a nice one!
There is still room for debate on some of your design decisions : For instance I'm not sure it was a good idea to introduce checkpoints as circles instead of lines, I sometimes missed them and felt very frustrated from having to do a puzzle again; I feel like this shouldn't be part of challenge.
Some slightly less punishing hitboxes might also help without affecting the difficulty too much.
Anyway, thanks for that; it was a good entry!