Sure, since the RC3, there's the "Auto Align" option in the Array 2S Generator > Extend X/Y Size mode and currently, the Auto-Align feature "replaces" the multiple object creation. This option creates an array aligned automatically with each sub-spline. This mode is very suitable for roof and panels. Two modes are available. For both modes, the Z-axis is always perpendicular to the plane formed by the spline. a) "X --> XY": X-axis is parallel to the RailClone XY plane (considering local axis of the object). b) "to Spline": X-axis is aligned with first Spline's segment (you can use "Make first" vertex and "Reverse" spline to modify alignment). Attaching screen-shot.
Hope that helps.