One thing I noticed is that the GUI of something like Cubase is NOT designed to be used with a touch surface. I saw many attempts to hit tiny buttons that all sit next to each other getting wrong results, or unrecognized input.

I'd say something like a full sized trackball like this http://www.amazon.com/Kensington-Expert-Optical-Trackball-64325/dp/B00009KH63/ref=dp_cp_ob_e_image_0 would be a more reliable input source.