You can't zoom into the preview map from that screen. Once you're in the game, you can view the 2D map by pressing the controller touchpad once (if you hold it in game, you get the instructions overlay).
The four arrows at the cardinal points and the zoom scale make it look like you can use that map, maybe it was something Dovetail were intending to implement. But then saw a bee or something outside the window and forgot all about it.
It would be a whole lot cooler if we could so you coud sort of preview the route prior to starting off. Once you're in the game, the clock is running so I always feel sorta rushed when checking the map in game. As a workaround, I keep my iPad nearby with a route map and timetable available for the service I'm running. Can also pause and check the objective list for a list of stops and times due.