This is such a clever idea; it ended up mind-bending enough that I had to skip over some levels, but the concept is really sound. Also liked the feel of the music with the vibe.
Only issues I had were controls. The isometric camera angle made me hesitate quite a few times, and/or make the wrong move (though the little drawing really helped!). But more obvious to me was the combination of mouse and keyboard controls. If a game is mainly controlled by the keyboard, I want to be able to restart a level if I sink in the water without having to reach for my mouse (same with the right-click controls for switching view).
Overall, very cool!