+ Info : When i put my Physics behavior on the sphere, the sphere starts to vibrate and my Camera Layout to bounce... anybody knows what is the reason?
When physics objects are colliding without much speed/movement, apparently the physics behavior tries to "shake" things up since the recent versions.
You should read the tutorials about basic and advanced physics.
Play with the "stepping mode" and "stepping iterations" (check the manual entry).
The ball hasn't enough momentum to move and just ends stopping on the plane surface of the box.
The camera shaking is probably due to the "Scroll to" behavior that is probably set to the physic ball.
But to really help you we have to see your capx, you should post it.