I think having a checkpoint might have helped. Also I would have liked to have a small feedback when i die in the game instead of just a quick restart.  Other than that I liked the simple visuals and the overall game.

Just one doubt, I didn't got the point of inversion. Is it just to complete the level or it served another purpose in the story?

How to use dash? Which button?

I think the game is unbeatable. On the way back when you need to go under the spikes, you cant.