SpeedyBall

(follow up) And combine that with a rather high acceleration value... Test it out for yourself and see if you like it :)

It's a lot better now. Just one thing that's really bugging me: When the ball is in air, and you move towards one direction. After that (still being in mid-air) you go the opposite direction. Something weird happens with the momentum... It instantaneously flips and the speed towards that direction seems increased as well. That's why I think a slight acceleration would be helpful (but not too much of course, you can put limits to this... for example if(Velocity.x > MaxVelocity.x) {Velocity.x = MaxVelocity.x;} (that's C syntax, but you get my point)

the ball respawn in wrong location, so once you jump off the edge, you lose the game as the ball are all lose

Thanks for your comments.

Shadow of the ball - thx, I'll try that.

In the first test versions of the game the ball moving was accelerated (to left and right), but then the gameplay was much harder.

Yes, I meant the accelerator as an option to get higher scores, but you can do the tracks in time with the lowest speed.

Couple Suggestions:
-Restart key
- Let shadow of ball should point out where the ball is on the track (so the lightsource should be perpendicular to the track)
- Add acceleration to the ball (instead of the instant velocity it gets now when you press left or right)
- Like CharmDragon says, give the ability the slow the ball down (unless you meant the speed increase as a punishment?)