Here's a few more things to try:
1. 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.)

2. Tip: Purge the Downloads Queue!

3. You could try removing all versions of Java installed, reboot, reinstall Java using the "Offline" installer http://www.java.com/en/download/manual.jsp

BTW the test page for the port is http://www3.limewire.com:6346/ & still works for me. Should say test worked.