When using an assembly with vertical edges, what happens when a Corridor datum surface is extracted i.e. vertical edges are not permitted in triangulated surface??
that should not be done with modifying the intervals of your (normal) contours. For creating contours with specific (user-defined) elevations you should look into DGM-properties and "Analyse" for "User-Specified Contours"
HTH, - alfred -
I do that as a matter of course, but in the screenshot that would mean a vertical face at the edges??