Small 4 x4 around the tree layout question I'm working on a small around the tree layout that is about 4x4. It has a small mountain and a tunnel. I plan to cover the layout with Woodland scenics snow. My question...should I ballast all of the track or just small sections? Should I be concerned with the snow material getting into the engine mechanisms? A small steamer will go around the track. Radius will be tight so I don't have a lot of options there.