Cool idea! I don't understand why it's jerky sometimes though.
Also, I'm not sure if I should play it like that or not, but I pressed the MMB on the character and used the free scroll to move it with the mouse. The only problem is that the vertical scroll is larger then the horizontal so the speeds vary for each direction and I hit the walls often :D
The checkpoints are good, but maybe make them in specific points instead of the last safe point the character is at before hitting a wall. Because more often than not, I keep hitting the exact same spot several times when respawning until I realise I have to center the scroll again. Still, it's possible I'm having this issue because I used free scrolling instead of the bars.
*EDIT*
So while I was writing this comment closed the full screen mode, and when I returned to the game that made me escape entirely out of the E.M.O.G circle of doom!! Definitely a bug haha