"I seem to have got it to run smoothly by blocking ports 80, and 6660-7000 (irc)"

This worked for me, too. Previously, Gnucleus was crashing on my Windows 2000 Professional system whenever my firewall (AtGuard) was running. Whenever the firewall was disabled, Gnucleus worked OK.

Anyone have a list of the ports and inbound/outbound permissions Gnucleus needs in order to function properly?