This is a SP2013 Bug report.
Microsoft, please provide a way for partners to submit bug reports to your products. Opening an incident is not the way it should be. Partner should be able to open bug reports.
I am using SharePoint 2013 Server Version 15.0.4535.1000 (August CU). I have verified the problems with three different environments.
Problem one:
The rating control is broken, better put the Javascript is broken. It only works after reloading the page with the star rating on there. This applies to Wiki Pages as well as Video player pages. A desciption of the problem and a solution is found here:
Problem two:
The UserField Control is broken on Video Player pages as user profile images are never displayed. Why? Because the URL Value is encoded twice!
The URL shown to the images is http://my.site:80/User%2520Photos/Profilbilder/wichtig_MThumb.jpg. See there "%25" in there? It's an encoded % - it should of course read "User%20Photos", nobody knows why you chose to include a space in there for such an important location. If you look at the codebase of Microsoft.SharePoint.WebControls.UserField and the Render method, you can tell that the url value for the image is HtmlEncoded twice if NoCAML = true. Unfortunately NoCAML is always true in SP2013 - setting NoCAML to false via SharePoint Designer fixes the problem of the user profile image, but reverts to the old way of doing stuff.
So two problems with two workarounds, but ultimately they are bugs. Please let us submit bugs so we can help make SP a better product.