I got my girls to go to the coop without locking them up 24/7. They free range my 1/2 acre yard and always (touch wood) put themselves up at night and are on the roost. All I have to do is lock up. It was July when I got them and temps were 100* here so locking them in the coop during the day would have been a death sentence. I only locked them in the coop at night. Putting a light on didn't get them to go in. They would still bed down under the coop in the run.
Here's what I did:
First, before they knew the coop was where they were supposed to sleep, they were locked in the run 24/7 (which connects to the coop) until they would go to the coop on their own at night consistently. I moved food into the coop and the water was in the run so they'd get comfortable with going in and out and with the ramp. When the sun went down (but it was still light out), I put them into the coop and locked them inside. I made sure to get up early to let them out.
Several days later, they were more comfortable with the coop and I could get them to go in without having to pick them up and put them in. Usually I herded them in but I think I tossed some mealworms in a few times. After a week, maybe two weeks, they were putting themselves to bed consistently. When I added some more birds, the newbies just followed the others.
Their roost is a 2x4 with the wide side up and is high up in the coop (but they can reach it). I try not to mess with them once they are in the coop as it's their "safe place".
FWIW, the nest box is level with the floor of the coop. The coop is about 2 feet off the ground. The roost is about 3-4' off the floor of the coop (probably 5' from ground level). Since my coop is designed more for summer than winter (winters are mild here), they have vent windows next to the roost on either side so they probably feel the full height from ground level once they're on the roost.