The "Cuts along curve option" allows the user to select a leading curve. The generated toolpath is orthogonal to this leading curve so the cuts do not have to be parallel to each other. Please note that the cuts should not cross over each other. This can be caused by a not appropriate leading curve. In such a case, you won’t get an acceptable result.
Hit the "Lead" button to select the curve. Note that the contour direction defines the cut order.
In this example you can see the leading curve and the generated toolpath. It’s important that the toolpaths at the edge of the drive surface do not each other.