I really like the atmosphere of the game, with the art, music and sound effects, congratulations!
I found the controls to be really difficult. I really didn’t understand how exactly the sling direction is measured. Usually I’d set the direction carefully, cancel the move, and then make the sling without moving the cursor so that the direction would be where I wanted and I could go farther. But then I got to a part with some moving platforms and they always changed the sling direction even if I didn’t move my mouse, so I wasn’t able to beat the game =/
Oh, and for 2 times I just jumped from the big arrow sign in the first area, before trying to kill the flying enemy xP