The execution method of the ActionHandler interface has an ExecutionContext parameter. You can use that to pass values to your action handler using process variables. Think of as a per process blackboard ;)
You can define process-wide actions as well as actions bound to exceptions, transitions and tasks (although I think these actions can be referenced from anywhere withint the same process too, gurus is that correct?).
Access the list of actions: yes with getRuntimeActions()
Get access to other processes? I guess with:
Hope this helps
Thanks it helped :)