I am currently running the trial of sketch up pro. I have imported some contour lines, which were splines in cad. I have raised them in sketch up at the desired heights and then have tried to drape them to create a terrain with sandbox but nothing happens.
Some things In SketchUp are not simple. I was going to list things for you to try, but if you have a way to post the problem file, we could fix it out and then tell you how it could have been imported correctly.
There are several different varieties of the controur set that I was experimenting with, some with grouped lines and some with the lines exploded from the group once in the correct positions (Far right)
Thanks in advance if you have any luck with solving this! Ive spent so long and don’t feel like I’ve made any progress. I can also send through the cad file, however the lines wont be raised to the according heights so probably wont be as useful.