As has been mentioned by others; jump = space, not up arrow.
Hitboxes for the saws makes it impossible see where death will hit you - you don't even have to get close to the ruddy things for them to kill you. Transitions between levels are abrupt and jarring.
It would also be nice to be able to turn off the rather intrusive music.
This is your first game, which is why you do get a point, and not a roaring empty non-rating.
