So as you may have already discovered, a number of people have been experimenting with making tweaks and modifications to both the custom observer ui system that we have in place for SC2, as well as modifying the UI for all of your own maps, mods, and games. We've seen a few wonderful resources available to people such as Helral's Override tutorial over on SC2 Mapster: http://www.sc2mapster.com/forums/resources/tutorials/20323-ui-sc2layout-files-override-method-aiurchef-method/ as well as other documentation that has been released by various individuals. In order to have a "one stop shop" for all of the custom UI needs you may have, we've created a central thread where you can ask your questions, share your tips and tricks, and help others who may be experiencing issues with their own UI. Feel free to ask how things have been done, whether or not things are possible, and other general questions.
Thanks, and we look forward to seeing what you guys can do!