Not sure if anyone else has this issue but in every game I play at some point the UI disappears (sometimes it freezes the menu of the last selected unit) and I am unable to build or chat. I can only select units and move them around but I am unable to do anything else unless I close out the game then reconnect.
Although this same problem has been reported once befor and i know its a known glitch but the U key has the exact purpose to make the UI turn on and off like this. See if it helps, if you havent already tried.
