Hi,
Basically you will need to build a custom action for each individual component, because each have their specificity. For the slide, you would deal with a float, for a button, a different system that would instead trigger an event when down and/or maintain a isPressed flag. etc etc.
The other thing: Depending on what you want to achieve, you might simply have iGUI do the work of gathering infos, and in one go communicate it to fsm, instead of fsm dealing with each and every widget on screen.
Could you elaborate on what you intend to do? and we'll take it from there.
Bye,
Jean