I took everyone's advice and placed treats up there ramp and a little in the coop for the past 2 nights. It looked like tonight I was going to have to do a round up after dark. I was coming back to the house and turned around to take one last look, and they were all marching into the coop. My son and I went back a few minutes later to close the door. One is roosting and the other three were in the nest (despite putting in some small pieces of lumber to try to keep them out). I think I will let them get by with being in the nesting box another night, just to make sure this was not a fluke. If they go in on their own tomorrow, then I will figure out something better to block off the nest. Thanks everyone for the help.