I think the paths (as well as scenery) won't move with the terrain as it would be more often than not broken after finishing it. Everytime you see grass turning into rock probably means that edge is too steep for a path. if you would lay your path and then start terraforming the path would need to turn in to stairs and work around your terrain. In my opinion that would just way to complicated with all the possibilities you have when terraforming. So do the terrain first and then lay out your paths however you like [happy]