I'm not too sure about the static IP for every computer but I'll ask someone... keep an eye on this thread
If your router has UPnP enabled by default, did you select Use UPnP from within LW's options > advanced > firewall config? Apply to save a change. You could try this & see what happens, give LW a while (say 1/2 hour) to settle down & see if the firewall icon disappears.