"You are no longer able to modify the Blizzard XML and Lua files."
And there was a great disturbance in the Force...
as if a million voices suddenly cried out in terror as their mods were suddenly silenced...
"What a crazy day it has been on ui.worldofwar.net. Well over 100 updated mods have been uploaded by mod authors, too many to list here, but if you have been experiencing mod issues then make sure you grab the latest versions. Thanks to all the mod authors who have updated so quickly and uploaded their new versions or new mods to the site."
"The low bandwidth version of wowinterface has been enabled because of the World of Warcraft 1.10 patch. Our site will go back to normal and this made an optional style again once traffic dies down in a couple days. We apologize for any inconvenience this may cause you."
Customizing the interface is a very technical endeavor, and you should not attempt it unless you have a good working knowledge of XML and Lua.
(* Actually there were a ton of UI Patch changes.)