Try abj's fix in post #26 here
http://www.gnutellaforums.com/showth...&highlight=tab

Or, if you like, you could try VLC player (you might be sick of trying all these different players but it's just a suggestion). It's free & very reliable. Choose the nearest mirror for download.
http://www.videolan.org/vlc/
You'll have to launch/preview files from their folders outside of LW