All previous versions of Quick cache worked great for me.
The latest version returns only a blank screen. I am using WP version 3.1, the latest version as of the date of this post.
Re-installs of QC have not changed anything. I have not changed any plugins since the last version, and shut off most plugins to see if there was a conflict. No help.
Thought I would leave a post here, since QC is my favorite plugin:)
In troubleshooting, I noticed QC no longer deletes cache files for me. Since I changed hosts in November, it is unclear to me whether there was an issue with host configuration. I had set permissions on content/cache to 777 just to make sure.
Hope that helps someone. I will go back to one of the more complicated cache plugins, which in testing were also not as fast as this one. Primo is a quality service, and I am sorry I was not able to successfully troubleshoot this issue for them.