I could not install limewire pro on my imac 233 mhz OS 8.6 When I double clicked the installer it was sending everything to the trash. Thanks to someone else on this forum, I was able to finally install and I immediately started sharing files. Here's the solution that worked for me.

First, go to control panels and select extension manager. Next, disable extensions by clicking the box that is checked next to "extensions folder." Then restart the computer and hold down the option key until it restarts. From there just double click the installer icon and the wizard will pop up and take you through the process. You do have to enable extensions after you intall and then restart. It worked for me, hopefully it will work for my fellow mac users. See ya!