Hello and Greetings!

I also was having this issue for one of my clients. He is using 64 bit version of Windows 7. I thought I would post what I did to get past the "permissions issues":

Uninstalled java + FW...
Ran installer as administrator...
During the installer it asked where to install program...
I clicked browse and told it to install in the /Program Files (x86)/FrostWire
continued the installer without issues or error.
The default location that the program was installing to is restricted by the Windows Account control...once you specify the correct folder, the program runs without issues. This is something I think the authors of the program
(FrostWire) should take into consideration during their next update release...

Cheers