Love the concept and very Creative! I was already impressed before lvl4, but lvl 4 was a bit mind bending and a lot less forgiving than the previous levels. I thought lvl 7 was easier than some of the previous levels.
The controls felt a bit weird and took some getting used to, but they were probably necessary for he gimmick although there might still be some room to tweak it to make it feel a bit better.
Great work! Really enjoyed it!