Here is a sample that illustrates how to use the same "object" from multiple custom activities, based on this MSDN forum post. This is a solution with a sequential workflow and two custom activities that each have a single dependency property of type...

This is a sample that shows how to use the InvokeWorkflowActivity from within a state machine to invoke another state machine workflow. The "host" workflow then waits for the invoked workflow to complete before it completes. Steve Danielson [Microsoft...