Here is an example of how it works. I suggest you watch in full screen!
As for the fingers, I was going to put in drivers, but I decided that for the project, it would be just as efficient to rotate and translate the joints, as I am not required to animate this character for the project.
I finished up by locking the translate, rotate and scale of my facial controller box. As for the NURBS circles, I limited the movement, so that they could only translate on the Y axis (X axis in the case of the smile controller) and only within the controller box.