I'm sorry you have problems with the curbs, but in this case there are multiples ways to define this preset. Please, let me to explain:
1) Depending of the scene, some users may use the spline to define the start of the sidewalk, the road or any other point. In this preset we choosed that the curb is aligned with the road, but you can modify it easily: change the Y alignment of the Segment from "Bottom" to "Top".
2) The direction of the spline also is significative here. You can reverse it editing the spline, or from the Generator properties (Geometry->Reverse).
3) This preset uses vertices of type "Corner" or "Bezier-Corner" to define the Bevels (miter joints). Your spline use corners for all vertices, so RailClone generates a bevel for each point. The type of vertex used for Bevels is defined at Generator->Rules->Corner->Vertex Type. In this case, i suggest to modify the spline, setting corner vertices only at mitter joints, bezier-corner or smooth for the others, and setting Generator->Vertex Type to "Corner". But other combinations may work as well.
Take in account that we include these presets as a quick way to create predefined objects, but users may require to adjust them according to their needs. Also remember that you can create your own libraries, editing the including styles or creating others (see here