I installed this on a woocommerce 2.0.4 dev-evironment with a responsive theme "replete from kriesi" and also installed the plugin Enable Media Replace.
In the media library Media > Retina there is a lot of space between the lines see screenshot here
also the sizes below the image are missing as described in the manual, as well as the re-upload button.
In my settings I see also an option for html rewrite, for which I did not find the descrition on http://www.totorotimes.com/news/retina-display-wordpress-plugin/
and beside it has worked to generate all images, it does not seem to work. I switched to debug mode, disabled styleshhets with firebug to see the image properties and no image has the retina ..@2x..
I tried in server and client side mode.
any idea what is wrong with me?