I wanted to give the Duplicator plugin a test run and used it for the first time on my site bluelimemedia.com hosted at Dreamhost and using PHP 5.3 and FastCGI.
I have the latest Duplicator version installed - 0.3.1
and WordPress SEO version 188.8.131.52
When I first installed the plugin and clicked on manage, all I got was a blank screen when I went to manage the duplicator and set up a package.
I deactivated the WordPress SEO plugin and was able to use the Duplicator. Since, I'm only duplicating once, it's no big deal, but I think that there might be some sort of conflict between these two plugins.