In order to enable the hover functions, you must change the setting in your admin panel to allow ratings to be unlimited (versus once). By doing this, you can hover over the images and you will see them working without being logged in. If ratings are set to only allow once, you must be logged in before the hover affect works. Hopefully, this will be fixed in the next release as you have to be logged in (regardless of which one you choose) to actually rate a video. So, it shouldn't matter whether or not you allow unlimited ratings or not.