I just 'evolved' to 1.4.5.0 and when I closed Gnucleus and started it up again, it would crash on every attempt to use it. This is running on Win2k. I experimented with blocking certain ports, and I seem to have got it to run smoothly by blocking ports 80, and 6660-7000 (irc), I didn't see why it connected to an irc server on startup anyhow.
If you experience the same problem, try this.