Not sure of what you wish to do with this in Blender…
But just exporting the contours to Blender and have a mesh surface is far more complicated in Blender than Rhino…There is a Rhino>Blender Plug-in to bridge between, think the only requirement is the .3dm must be textured…HERE
I took your curves and converted them to mesh, then joined. Added a subdivided plane for the mesh… took your curves and used them to Knife project to the plane with cut-through ( did not separate… that cuts the plane along the curves making four face objects…selecting highest first, add height with Grab and grid-snap as well as proportional edit…repeat for each cut curve.
Note: I should have placed the plane inside the ends of the curves but I snapped to the ends and that made a slight mess on the edges…
