Okay, I've got two more things that came to my mind regarding your problem.
Firstly, I assume you see the brickwall in front of your globe in the left bottom corner of the LW window.
It is possible that this brickwall does not come from your (offline) firewall, but from your Antivirus program (in my case it was AVAST). I went into the menu of Avast and put the comeplete LW folder into my exception list. After that I restarted LW and the firewall dieappeared instantly. So, that might be a way to solve your problem.
Secondly, after reading some more about ISUnet, I came to this article:
http://www.isunet.net/support/support_disconnects.html
I don't know whether this is connected to your problem, but I thought I'd let you know anyway.....
