Viewed from the end of the layout extension, the photos show the two tracks as set into "concrete" for a distance of about 48 inches or so, so far anyway. I've used a couple of different greys to colour the concrete sections, and followed them with a dark wash or two over some of the sections to try to represent replacement or repaired sections.
Also, the warehouse track on the left has been ballasted now. I've put a wide gravel shoulder area between the roadway and the warehouse. I intend to have a transport trailer or two "temporarily dropped" in that space. There's some static grass growing along that area now too. I think my next effort will be to similarly finish the track spur and the open space on the other side of the road where you see it as just painted brown now.