Best UI out there! Seriously, thanks a lot for your work!
Just a minor bug I found when my bottom left action bar is hidden and I have a pet the pet bar is not aligned with Blizzard's pet action bar texture:

So I just changed Action Bar position to Bottom Row (which I have hidden anyway) to make the default pet bar texture disappear.
Another thing - I've noticed your combat text module is not available in the Elements option menu to be turned on/off. For now, I just deleted the combat text folder from modui folder to be able to use the original combat text (works without any errors).
Also, in Display options -> Toggle [brackets] on item links seems reversed - I have to turn it off to see the brackets, turning this option on turns off the brackets.
Oh, and the nameplates seem to bug out from time to time, and I have to target an enemy player to see his class color, sometimes it works without targeting, sometimes not so I found myself using ShaguPlates instead. Not sure what's the difference in his and your code but you might want to look at his code and implement it into your great ui!