To improve the feedback of the turntable, especially for the plate, a bit I wrote a simple DrawableGameComponent which draw’s a mouse trail. Simply call it in your game via:
Cursor c = new Cursor(this);
The component will register itself. You may need to adjust the elasticity, friction and the scaling of each Trail Point in the component to fit your needs.
Download: MouseTrail 1.0
Screenshots: MouseTrail in Curltable, Standalone
In addition I setup a little multitouch device like the one from here and used the TUIO library and the TUIO C# Client to have multiple Cursors. You will need to download the CCV from the NUIGroup too.
Download: MouseTrail MultiTouch
Feel free to use it in your Game.