Hi,
Unfortunatly, that would mean editing the official actions ( for portability), so within Playmaker, I do it differently, because of PlayMaker nature.
basically, you create your own input broker by having your fsm not rely on the unity set of input function but yours. and everytime you want to listen to a key press you listen to both the keypress AND a custom keypress flag that you can raise from another fsm.
so if an fsm wants to do something on y key press, it should not itself try to catch this keypress, but you should create a fsm that manage inputs and fire a global event "MY KEY PRESSED", that fsm will catch, and so these fsm don't care how ti was triggered, and you can fake keypress very easily then.
Does that make sense?
Bye,
Jean