Don't worry so much. I went out night after night when my chickens were that age, and put them up on the roosts, and turned around to pick up more chickens to put on the roost while the last bunch jumped back down, and then turned around to pick up more chickens while THOSE jumped off and went back to their corner, get the picture? Night after night, so frustrating... "OMG, what's wrong with my chickens, whats wrong with my roosts????" Feelings of failure and profound inadequacy... Then, one day, they decided the roost was pretty cool and... don't sweat it, they'll get it.