How to model a tapered bridge in a curved portion in Leap Steel?

The PGL of the bridge is a straight line followed by a horizontal curve. The curve portion starts at the middle of a span. Bridge deck is tapered for the straight line portion and constant for the curve portion. 

I tried the three different ways (Independent, concentric to align., custom beam path) in Member Group of Leap Steel to model the girder layout, but couldn't find a way to model it exactly as the plan shows.

Could you let me know how to solve this problem?

Thank you.