[cypher]

It can take them a while to adjust & as velma said it is a huge change for them so don't get too disheartened just yet!
If I remember rightly he's in an Alaska? It's a great cage but quite big for a little dwarf that has been used to a tiny tank so make sure there isn't too much open space, just use a few things like toilet roll or kitchen towel tubes, egg boxes or other small boxes to make some little hide aways.
Have you done the tissue trick yet, putting toilet tissue up your sleeve for a few hours then tearing it up & putting it in the cage, that will help him get used to your scent.
Other than that talk to him, even when he's hiding away so he gets used to you being around his cage.
Try hiding some of his food or some treats around the cage to tempt him to come out more.
He should begin to get a little braver soon.