Did you set up a static ip address before port forwarding? If you did not do it before port forwarding your router, then you will need to delete those port forward rules & do them again. You also need to set LW to port forward type of connection under advanced settings.

BTW I've never heard of LW 5.4.9 lol .. sure you have the version correct?

Also need to make an exception for LW in the XP firewall rules; Setting up an exception for LimeWire in your software firewall (click in link)