You can access this dialog from the following:

Ribbon: OpenRail Modeling > Miscellaneous

Creates left and right rail geometry. Geometry follows horizontal, vertical, cant alignment and track widening. 3D mesh model of the rail can also be created with this tool. Created rail geometry is a complex element that consist of components that represents each individual rail element.

Rail geometry represents Top-Center point of the rail. To obtain accurate results, if 3D mesh will be created, selected template should also have its origin at this same location.