Hi Tommy,
NGUI are simply gameObjects, so you can can already exercice yourself with a simple cube.
instructions:
1: create an Fsm on the GameObject you want to control
2: create two events: "RIGHT CLICK DOWN" and "RIGHT CLICK UP"
3: in the start state, add a "Get Mouse Button Down" action, set the "right" that sends the event "RIGHT CLICK DOWN". Add this event as a transition of that start state.
4: transit from "RIGHT CLICK DOWN" to another state called "turn"
5: in state "turn", add a "Get Mouse Button Up" action, set the "right" that sends the event "RIGHT CLICK UP"
6: transit from "RIGHT CLICK UP" back to the start state
and that's it, you'll get your behavior.
if you have trouble getting this to work, let me know, and I'll send a working sample.
bye,
Jean