This is a really cool concept for a game, and the puzzles using it were very well designed.
I had a few minor frustrations though, mainly that I would often realize I made some kind of mistake late into a level and would have to redo the entire thing to correct it. Maybe there could be some kind of ability to delete or redo the last iteration?
Also the movement felt a bit clunky, but that's fairly minor for a puzzle oriented platformer.
Overall great game!