I’m very interested in knowing if it is possible in Dynamo to: 1. select a surface, 2. enter a real number (an elevation that must be between min and max elevations). 3. create a civil 3d surface style with that elevation in the name. 4. modify that style to show only user contours ‘with only the above elevation’ specified. 5. extract that user contour as a polyline.
Doing this manually is very easy, but can become tedious if you do this a lot.