Hi, Try to separate rails and pickets to separate generators or upload the scene file so we can check.
When you use the scale mode RC will scale the segment to the section length (Spline section, Evenly, Markers) and if the original segment does not have too many subdivisions there is noting to jitter.I think in this tutorial you can see basic use of scale vs tile: https://www.itoosoft.com/tutorials/telegraph?back=page%3D8%26tag%3Drailclone
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