This addon is a pain to work with but can create a nice clean base to any fully customized UI. It changes the look of the game menu, character frame, achievement frame, talent frame, and lots of similar things. It also will skin supported addons and even turn itself off for addons that conflict. 

It also acts as a viewport addon and can change the actual area that the game renders. If you;re like me and have unit frames, actionbars, chat frames, and DPS meters across the bottom of your UI, why have the game in the background, allow the game to play in a window above that stuff and make it easier to see!

The included video goes through a lot of the features and customization options of the addon. The customization is unfortunately not intuitive so the video will help immensely. 

TESTED AND WORKING!

KNOWN ISSUES: Lots of small issues. mainly changing options requires a /reload to see