Hello mrthoms,
If you wish to run server and node instances of PhotoScan on the same computer, you need to do it from two separate terminal windows.
Server should be started first, before running the nodes in the network, as they will be trying to connect it.
Server is controlling the jobs and managing the nodes, if new node is added to the solution, server will check, if there's any task that can be sent to the new node.
The tasks themselves should be started from the client GUI, providing that the network preferences tab is filled correctly.