I just copied the paved_roads.tga, paved_roads_constructed.tga, c_paved_roads.tga, and c_paved_roads_constructed.tga plus the
ones in the \construction subfolder and then renamed them. I started
to edit them and try to put something like curbs on them to make them
more "highway like" but realized two things:
(1) I stink at graphics stuff.
(2) You have to do this under each culture. That's 6 times 4 .tga
files if you leave out greek and mesoamerican.

Now I just live with them looking like paved roads. Didn't
SilentResident mention something about having made building
cards for them? Maybe he could post some nice graphics.
Hint, hint.