Good tip. In Maggie’s case she walked right in but I can see that might not work with one of the Roadrunners.One last tip: sometimes it's hard to catch a chicken. They get scared and start running.
So, it's a lot easier to lift a hen gently off the roost after dark and place her gently into her box. She can sleep in the box without any worries. If you make the appointment first thing in the morning she won't have to be in the box for too long.