Run time Error when physics is added to a procedural model

[Game]: Error: Unexpected exception. SiliconStudio.Core.ServiceNotFoundException: Service [IPhysicsSystem] not found …

Demo proyects Works fine. But when I want to recreate it by my own then I get that error when physics is added.
Where is the problema?

Physic System is an optional module of Paradox. If you want to use it, you need to add it explicitly from the code:

        //physics needs explicit initialization
        GameSystems.Add(new Bullet2PhysicsSystem(Services));

Note that in future it will be possible select optional modules from the Game Studio directly.

Here it is what you have to do exactly (in the source code from Visual Studio).

public class MyGame : Game
{
protected override void Initialize()
{
base.Initialize();

        //physics needs explicit initialization
        GameSystems.Add(new Bullet2PhysicsSystem(Services));
    }
}