Frank,
Attached is your part with a var-sec-sweep protrusion built on your curves. I think you are making error at using edge on your sections. As the name states variable section means that the shape of the section changes along the length of the trajectory. The trick is to draw your section relative to the end points of your trajectories. Notice how I dimensioned the section on this protrusion. The actual shape of the section changes as it follows both curves.
Hope this helps,
Ron