Smileh This shader effect is not related to bounded or unbounded scrolling. It's a fullscreen effect, whatever is on screen.
Here is a simple Capx to show you how it works.:
https://dl.dropboxusercontent.com/u/13847313/Scirra/ShakeCamExample.capx
You will see a ShakeEffect layer. You can use a layer like this for all your fullscreen fx.
In order to affect all the other layers behind this one, I use a trick. I include as first shader fx on it a NoiseMask (set at 0). After this one, you can add the fullscreen shaders you want.
The important thing to know is to be sure you have at least ONE object (whatever it is) on this layer. (or the shader won't be applied)
I hope it will help. I'm not good at explaining things. ^^