question

You're passing in the Processor for the Task Executer / Dispatcher field of the Create Task Sequence activity. That's what the error message in the system console is telling you:

time: 262.947546 exception: Error: Bad Task Executer reference in create task sequence activity "Create TS" in process flow "ProcessFlow"

You need to select a an object from the Task Executers category of the Library to send the task sequence to. With the way you're building your Task Sequence, you should click the remove button for the Task Executer / Dispatcher field on the Create TS activity, uncheck Wait Until Complete on the Custom Task activity, and then specify a task executer in the Task Executer / Dispatcher field of the Dispatch TS activity. If you do those steps the message will be sent once the task executer gets to the task sequence. I gave it to the Operator and it worked just fine.

I would recommend reading through the user manual with regard to the Task Sequence activities. There are multiple ways to use them. Messaging isn't used very often with Process Flow as it's often easier to keep all of your logic in Process Flow (in your case using a Custom Code to close and open ports) rather than have logic spread throughout the model.