Wing Fat - once you have a station up, which you have 1 track to, you can add 2 more. To add the 4th, you must turn it into a Terminal. It doesn't matter what side of the existing track you use. If you try to put a double track in B4 you put up the Depot (lowest station), then you only get one of them.
Arthur39 - search for Hooked on Railroads on the internet and upload it there. If I don't get to it, there are lots of other that will.