Right ... I thought you had installed pro. but it seems you cannot install anything!
You need to uninstall your previous copy of Limewire.
go to Applications. If there is a folder called LimeWire delete it. Go to HD>Users>Your name>Library>Preferences>LimeWire... delete the folder "LimeWire"
Keep finder open and click on file >find seach for "limewire" and you may find LimeWire.dmg and LimeWire.pkg. Delete them also, but if you can't find them don't worry, you may not have them.
Now got to Limewire
http://www.limewire.com/english/content/download.shtml and down load again. Use Safari, not another browser to do this.
The first thing you should do when you get Limewire working, is follow the instructions in my first reply to you and with a bit of luck you should be up and running. Any problem ...give us a shout, sorry for the delay, the forums have been on and offf all day!