The SARN routes on the download station (once all are merged) provide a good layout of Adelaide from Norlunga to Mt. Lofty.
Unfortunately, you must use the surveyor to add stations and industries.
I am currently trying to update all the signals, stations, and some industries for my own but it is slow going.
If you are comfortable with using the surveyor, give this a try.
I have started on an extension to Mallala but framerates are a serious problem with a route this big and even with portals, it is alot of boards.