PocketLibrarian, I'm the author of Pi Scan so I'm happy to work with you to debug your issue. You can PM me or start a new thread (this is not the right place for it).
Other than that, I'd say that TwoCamControl is a great controller system. And Using a USB trigger like Konos93a describes is also a reasonable alternative.
Introducing spreads: command-line workflow tool
Moderator: peterZ