Vince,

I find the roads look best when viewed from a distance rather than close up. As you get closer, you see distortions caused by two factors: one, the road map generated from the bmp terrain tends to give a stair step look, which in Bryce can be mostly smoothed away; and two, the generated roadbed and center-line texture maps have jaggies caused by curving lines and they become more and more visible in closeups. Both these can be corrected to an extent by tiling the terrain so roads on a given tile are larger and have less of an elevation change, but it's a lot of work to piece the terrains and road together. Net, I'm not sure it will do what you are trying to accomplish. You you can make a couple of test roads and see what they look like but I'm guessing they won't work for your application.

If you want to talk more, you can send me an email via help@shapemagic.com I have done some work on a version that creates an actual 3D model that his more precise but it's far from complete.

Rich