Create a 3D Solid model with Draw 3D Model command.
In Layout/alignment enter the alignment drawing, in Profile enter the drawing of the profile, and in Cross sections enter the drawing of the cross-sections of the railway. Data sources can be either in one group or in separate DWG-drawings.
In the Select alignment select the main alignment and define the starting and ending cross section.
Check planimetry quantities you want to create a 3D solid model from.
Check Align to connect the consecutive planimetry polygons along the alignment. Otherwise, it connects the adjacent planimetry polygons with sectional straight lines.