No, point-to-point (or full-fare) tickets should not be added to the Rail Planner app, as the app is designed specifically for your Interrail Pass journeys. If you add your full fare journey to your Pass, it might accidentally use up one of your travel days that you'll need later in your Byway itinerary.
Instead, scan these tickets at the gates or show them to the conductor on board.
Point-to-point tickets are clearly marked in your Journey Guide with a blue notice, like the example below:
