The vertical elevation data is not exported with the alignment. To get the expected result, you may try to create a corridor with a top surface. It's important to have a surface to transfer your vertical profile.
Hope this helps,
Can you not just export a 3D polyline from the corridor "crown" and keep the elevations of that 3D polyline to represent the road C/L? I can't seem to use these 3D Polylines and generate roads, but I think there is a way to do that without generating a surface.
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