Hello everyone,
I've just started putting my hands on Stencyl and I'm very happy about it!
Unfortunately, almost immediately I stepped in a problem that I don't know how to solve.

Let me explain. To motivate my learning path, i'm developing a small silly game where the following happens:
1. a balls is drawn on the top of the screen, which is empty, and when the player touches the screen...
2. ...the ball falls from to the ground (screen border) and, using physics, bumps around until it stops like a real ball would do...
3. After this, another ball is made avalaible and the silly game starts again from step 1
Of course, if the 2nd ball hits the 1st ball it will have to interact with hit, moving it until both stops. And so the third, the fourth and so on until the screen if filled with balls...
Ok, I told you the game was silly, if it could even be called a game

First of all a simple question, is the box2d engine able to manage a screen full of balls interacting, without overheating the processor? Or should I use a simpler engine?
Of course, after the first row is filled with balls, those balls won't move much, reducing the physics calculations.
And here comes the second question, far more important: how could I generate a second ball, keeping the first one in game, and start again from the 1st step with the new ball?
I'm just a hobbyist developer, so excuse me if I write bullshits, but I think that in some way I have to number each ball and control them separately. Maybe I can have instances of the same ball and pass the player control from instance to instance?
Well, if I look confused it's because I am!
Looking to tutorials on the web, most of them use as examples spaceships that after being destroyed start again from the beginning of the levels.
Or balls that will disapper out of screen after the player miss the hit and then appear again in the center of the screen.
In each one of those examples the actor:
1. disappears
2. appears again.
On the contrary, each of my balls (!?) remains on screen until the end of the game, so those tutorials don't help

Ok, I think the problem is clear now.
What I 'm looking for is someone who point me in the right direction.
Just some indications on how to do it and maybe, if there's some technical slang involved, the words that will help me in finding the way out of this.
Thank you very much for your support!
Cheers
Enrico
PS: Hope I don't miss the right