Algodoo

After playing with this, I now understand how it's different from my version of the game. In my version, the ball stops accelerating when the arrow keys are released. In this version, the ball continues to accelerate, which would make the game more difficult.

As I mentioned in the comments section of my scene, please go ahead and make whatever changes that you want to it and post it as a new version. Using gravity control should make the game much more challenging.