If the bug test is still giving a False report for incoming, then it's still a firewall issue of some kind. Question is for what reason. Are you sure you don't have some other firewall on your computer. Check your control panel to see if there's any other.

I see you're using XP SP2. It might be an idea to use this 3rd party patch. http://www.lvllord.de/?url=tools

Downloading
 

Yes, still false.

I can't see anything else called Firewall apart from Windows Firewall in Control Panel. I haven't attempted to install any 3rd party ones.

I tried running the Patcher for TCP/IP.SYS but it aborted saying this version of Tcp/Ip.sys is not supported.

Trevor