Once you have wired up a Gpio button, this can be used to control Box Of Stops in exactly the same way as any other [[Trigger]].
If In [[Configuration mode]], if you click the plus icon to add a trigger to a [[Stop]], [[Coupler]] or [[Combination]] in the usual way, then the screen will wait for you to press the new input button. Assuming everything has been wired up correctly, the screen will then confirm which button you pressed.