Couldn't figure out the double jump level. Was trying to slide/ride on the wall to jump but couldn't figure it out.
The hint/instructions on that level hitting w+s (hard combo to hit) or even alternating didn't seem to do anything in combination of other parts.
I'm probably not your demographic for this, but the UI was very polished, as well great settings for the game to map controls. One of the better entries I have ran across as far as polish, but couldn't quite figure out (even after looking at controls) or get the feel of the game.