The damage type symbols above the monsters are not displaying for me, only the numbers. Well numbers and the irksome "immune" or "save". I've only found one pertain net check box in the UI section which is set correctly, I think. I've not found the info searching the forums with various combinations of "damage" "type" and "disply" so far. What needs to be set to make them display again?
"Show damage type icons" is what you're looking for, I believe. It's pretty far down the list in the UI section of the menu in-game. Right above the second set of color sliders, if memory serves.