Those make really cool cages for cresties. I have seen several people using them.
I wouldn't worry too much about him skipping his worms. Probably just readjusting, when I rescued a crestie from Petco he wouldn't eat insects for about 2 weeks.
Has he eaten his CGD?
Oh an Joanna I have a question for you, where did you get the little yellow dish? Are they really deep? They look like they'd be perfect for feeding CGD.