lovley chicken coop

so from the pictures my understanding is they are roosting on the outside of the RED coop and you want them to go into the red coop at night a sleep? is that correct?
if what im saying is correct then what you need to do is put them in the coop in the late evening as sun is going down and shut the door and leave them in there for a few days with the door shut. after 4 days open it up and let them out.
see what happens. but in the red chicken coop is there a perch in there?
you could also remove the out door perch and then they wouldn't have the option of that roost outside!