Sure. First I will describe my architecture:
I have a gui with multiple buttons and GUICamera handles and treats all the incoming events via Playmaker FSM that was the idea.
The problem is if you do exactly as described here :
https://hutonggames.fogbugz.com/?W1111(attaching a NGuiEventsToPlaymakerFsmEvents to camera and send NGUI notifications directly) you will not be able to determine the event origin.
The solution: Create FSMs on your buttons that will listen to OnClick events and then propagate them to your main handler object.
Button(NGuiEventsToPlaymakerFsmEvents )->ButtonsFSM->MainHandlerFSM.
Like this.