Nice and fun game! Becomes more and more interesting as you progress more. I eventually gave up at the stage after the ice after the fourth time restarting.
Maybe a counter of how many retries are left would be helpful. I was also expecting the mouse drag to be in the same direction as the one I wanted to move to (not like a sling), but quickly got the hang of it. It was very convenient that I could "center" the sling anywhere by just dragging from that point.