to Mike Nielson:
I, too, have a Gatewood Cape and used it for a 5-week hike during Summer 2007, as well as other shorter trips last summer. Love it!
As to your pondering adding a netting skirt, here's my advice: Having used double-wall tents, single-wall tarptents, tarps, and bivies, I think that completely surrounding a tarp or tarptent with netting really exacerbates the condensation issue.
It's much easier to manage condensation if the netting is just a mozzie headnet or a hanging bug bivy that surrounds your head&shoulders. That way, air is freer to flow into the shelter and move moisture out.
Once you add netting around the perimeter, condensation rises dramatically. Thus, ironically, Henry Shires' TarpTent instructions say to leave the mosquito netting open whenever possible. I have 2 TarpTents (original Squall and Cloudburst) and love them, but they really do get a lot of condensation when closed up. Not a problem with one person, but with two in the tent your bags brush against the sidewalls and get really wet, in my experience. That's why I think his newer Double Rainbow design is so brilliant because it's configured so your bags are up against the mosquito netting, not the silnylon sides. Ron Moak at SixMoonDesigns has achieved similar breakthroughs with his Europa, Lunar Duo, and (I think) Refuge tents.