Yeah, I have this issue as well in Editor.
It looks like an issue with Shaders so I tried extracting the shaders into working/source and working/source/xpack2 and no go.
I tried extracting the shaders into steamapps/common/tq/resources and IT and xpack2 and no go.
Tried extracting the shaders to Database/Shaders and Database/XPack2/Shaders and no go in any version
I even tried extracting them to the THQ directories and no go.
I'm stumped.