I think they're fine. If you have a light now you'll never be able to take it out because the chicks will be so used to it that they'll cry for it when you take it out. They'll adapt to their new coop :)
They just need to get used to their new "habitat". I just moved my 3 chicks into their new coop yesterday and they don't want to go in at night either. Try putting their food and water in their at night (if it isn't already) and that may attract them to the coop. You could also try putting...