Hmm, not sure I have same problem but...
 

I've had excellent luck with all downloads from LimeWire to date with the exception of one; everytime I've downloaded Quark XPress 4.1 (Mac).sit OR .zip, and double-click it to launch, it only opens up a new LimeWire window. I have downloaded several versions from numerous hosts and of varying sizes but each time my Help balloon indicates that my Quark download is a "LimeWire Document". All other mpegs, jpegs, sits and zips have been successful in functioning. What's up?