Box creation is making the physics pause

Solution 1:

the problem is that in your down event function, you didn't passt the scene as context. I'm to sure which method you are using, but here an example what I mean:

  • If you are using the input.keyboard.on way (here the documentation):

    this.input.keyboard.on('keydown-DOWN', function (event) {
        // ...
    }, this); // <- finall *this*  is very important  
    

the final this is the scene, that you need to pass to the keyboard event-callback. So that the this in your function createBox points to the sceneand not to the browser window;