Can't see icons, or open bags.
 

http://prntscr.com/lv9or0

The LUI errors are related to Freetip, carg Bags & RealUI skins.

I've updated since 8.1 and use Twitch addon update. I've also redownloaded RealUI.

Blizzard changed the folder structure in 8.1. Double check that you're placing them in the correct place and that the client is too.