I just installed LimeWire Pro 4.13.0 on Windows Vista Ultimate x64. I first tried installing by just clicking on the installer and it hung on installing Java.
I then went to the Java site and downloaded Java 6 x64 version and again tried installing LimeWire once again the LimeWire installer tried to install Java and hung.
I then went back to the Java site and installed Java 6 JRE (32 bit) using the offline installer. I then tried installing LimeWire it installed without any Problems.
When I started LimeWire it showed a firewall in front of the globe and only connected to 2 host. I then checked the windows firewall and made sure it was allowed in the exceptions which it was.
I then configured my router for both port forwarding and upnp forwarding the globe disappeared and I got a turbo connection. I then did a search for a large file and started Downloading a file 200 MB file within 2 minutes I had 10 connections and I am currently downloading the file at 150 KB/s 50% done in 7 minutes so LimeWire works fine with Vista.
You can get Java 6 at the link below.
http://java.sun.com/javase/downloads/index.jsp