Sorry I can't help you, but I couldn't resist making a comment. It doesn't surprise me that their API doesn't work or that their system doesn't work like their support files indicate. That has been their MO for the last year.
I'd say most who signed up for reseller accounts are probably not using them to actually resell, but to gain a better price for themselves. Anyone who has read the Registefly horror stories would be nuts for staking their business reputation on registerfly's buggy scripts and unreliable back end support.
Good luck with your situation, and use caution before getting in too deep with customers to support.