Algodoo

cool!

Some help for it:
Don't use a gear to connect the two pistons. Just overlap them and connect the two pistons to the same flywheel.
Use circles and not boxes to spawn circles. They have better collision.
For the block, don't use polygons, because they have a very bad collision.
Use the grid!

All in all, it's ok!

Oh, and the most important: make a killer of 3 times the radius of the spawned circle. That's the secret!
Just don't put the block as a killer. At least you should make inverse engineering to another engine.

thanks for ratings.. i will make another