Also, you may try allocating 40 or more megabytes of RAM to LimeWire. You should only do this is you've got a larger than average amount of RAM. I think you can hold the control key and click the application shortcut and tell it how much to allocate. I don't have a Mac to test this with, so I cannot tell you for sure if this will work. Others have done this and seen improvement or a complete fix of the problem.

Does this help? Be sure to post again if you need more help! :-)