I liked the gravity changing aspect and the art and controls are great! But I do have one problem (which isn't really about the game itself, but rather one of it's levels). In level 5, it felt incredibly hard to fit the box down the starting hole. Whenever I tried to do it, it would just get stuck between the two walls next to it. (Keep in mind this could have happened because I wasn't doing it correctly or maybe I just suck at video games lol)
Other than that, I liked the game and the puzzles!