Ahh. So the viewer is connecting to LOCALHOST, much like one would with ssh tunneling -- got it! The special sauce is taking place entirely between magical NAT2NAT modules. (I had thought the NAT2NAT was handing off the derived IP address directly to your viewer.) Thanks very much for the insight. Now the remaining mystery is what's inside the NAT2NAT black boxes.
But I've buried the lede here -- my test from home worked! I think this is a really great proving ground -- I connected successfully from a viewer behind a consumer grade Netgear router to a server behind an enterprise grade Cisco ASA firewall! Definitely NAT 2 NAT.
(I was also able to do it the other way around. Chunk really makes assuming client and server roles dead simple.)
I find this very impressive. The speed was pretty great -- I even tried a couple of Youtube videos and they approached something one could conceivably call "smooth". And this was with default settings and autoscaling turned on. I repeated the videos with the LogMeIn Java client and they played far worse.
I tried running as a limited user on the home XP station first -- this did NOT work at all, in either client or server role. No lights. Pretty sure the NAT2NAT module requires admin rights. (Even doing a RunAs on InstantSupport or ChunkViewer did NOT work.)
Having trusty old ZoneAlarm 2.6 here allowed me to get prompts for each step of the 3 Lights process, which was kind of fun.
Upon closing the viewer window, the NAT2NAT window was usually left up and running; I don't know if that's normal.
For an alpha test this went almost disturbingly well for me. You and Rudi have certainly proved your point!
I now can't wait to see this go into the mainline UltraVNC and ChunkVNC, especially including a self-hosting option for an open source NAT2NAT server. (Hmm, I wonder how light a load NAT2NAT places on the server; one could probably handle hundreds or thousands of connections.) The repeater fallback you suggested would be even better.
You guys have finally got me excited about VNC again.
P.S. Are there UltraVNC and/or Repeater related dependencies here? Would NAT2NAT work with other VNC brands, or other programs entirely? What about direct file transfers? I would think that point to point video could provide better quality than Skype....