Quicktime playback doesn't work
 

I used Limewire 1.8 for several weeks and loved it. The program worked like a charm. I've just downloaded the new Mac version (2.1.3) and now none of the files I download will play when I highlight the file and click the launch button. The downloaded files also do not have a Quicktime icon, like they did with the 1.8 version. What is going wrong? What do I need to change? Thanks for the help.