I've discovered a bit of a bug with the api transfer functions.
If the transfer-conf panel has AGENTDIRECT selected, it's not possible to transfer using the API to a non-AGENTDIRECT ingroup without first going to the TRANS-CONF panel and selecting ANY ingroup that is NOT AGENTDIRECT.
Bug submitted on tracker http://www.vicidial.org/VICIDIALmantis/view.php?id=1330
I'm pushed for time at the moment or I'd look to patch it.
Install vicibox 10 iso, SVN Version: 3528, DB Schema Version: 1645
Just posting here in the meantime to see if any kind soul has the time to look at it before I do.