hey ash, Im not an expert or anything, I adopted my colony of 4 in October, and they were a breeze to bond with. They would crab a little but now they hardly ever do ( just little Hermione when she is woken up sometimes). I can now just stick my hand into their pouch and they all click and chirp and snuggle up to me . It's one of my favorite things.
I have been fostering a colony of 5 for an aquantience, and the youngest two are under 6 months and I don't believe they have been handled much. The will crab and attack the side of the pouch when they hear my voice (especially the little girl). I have been taking it slow with them and found that, even though she will crab at me and swipe at me, she doesn't mind me touching her so much. She is just scared.
I have been a little reluctant to do the bonding pouch with them, because they are not staying with me. So I don't want to commit to the bonding process completely. But I think that the pouch might help at least get her more comfortable around people in general. she does great in the tent too. It helps bring you down to their level.
The thing is crabbing is going to happen, they are scared. You have to let them know they are safe and build their trust, it can take time. I started out having a yougurt drop in my hand and when she would bite at me she would bite a yogie. after a few times she still acts grumpy but not as scared.