it looks as you have 2 drawings or is it all gonna b one? as for scaling it out how much room do you have to work with? do you plan on having this on a 4x8 sheet of plywood or something diffrent or are you looking for a shelf type of layout?
roads can be anything you want em to be of course it all depends on your town/city budget. not all roads are completly smooth. as for paint i use walmarts 99cent black paint in thier craft section.
try taking a pair of ruber handeld pliers and place loco on the dead track place pliers on one side of the jaw on live joint/rail and place the other jaw on the dead rail/joint or pich you connectors together.