sign up at www.list.nessus.org for the mailing list. It's helped me out a lot with learning the system. The first thing they'll tell you to do is to get updated to 2.2.6, but they will still probably help you get that issue resolved for now. They have a damn fast turnaround time on problems too.

I don't know the answer, but someone there will... It's just a good list to be on if you're going to regularly use that program.