So the issue I am having is in the third chapter of HotU. In Cania there appears to be missing textures and everything is floating above the the ground, like the plane that my character and all objects rest on is removed from the ground by several feet.

You may need the 1.69 Critical Rebuild, which adds files that may be missing from your installation. Download the HOTU Critical Rebuild file and run it.

Alternatively, you can try Sorcerer's Place and scroll down to Hordes of the Underdark Missing Textures Fix (the fourth file listed on that page). The file it links to is direct from Bioware's servers and is smaller.

I would recommend the Critical Rebuild patch as that should fix other issues that may be present.