I've tryed to upgrade LimeWire 3.6.14 on OS X 10.2.8.
There is now an installer and I gave my administrator password and launched the installation.
I choosed an Image Disk for destination.
Then, everything on my Desktop disappeared, and all my documents, library, etc.. folders were deleted.
It was impossible to recover them.
I think this is a major bug which has to be fixed as soon as possible!