I presume you have XP SP2. SP2 changes the firewall settings back to default. It also reduces simultaneous connections; see MS & 3rd party patches

Make sure you have at least Java 1.5

You may want to delete your LW prefs if you're using the same as before. Try deleting your LW Preferences folder whilst LW is closed; instructions here: Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.)

After this, do you see a brick wall in front of the blue world icon at the bottom of LW's interface?