There are many reasons downloads fail--I've had problems with my Mac settings, router settings, cablemodem, my ISP, old versions and just bad luck sometimes. However, I can download pretty successfully now with the new versions and a set-up I can trust.

If you're doing something "wrong", someone might be able to help if they knew what machine and connection type you use for starts. You can find much of that information in the "Sample Bug Reports" of the Limewire Options/Preferences.

Cheers