I have mine on the same network as the PCs. I also have ZIP drives connected plus a CD. And what with broadband on the Miggy also I just never have a problem transfering stuff between the Amiga and the world. Thing is that the files are just so small it hardly takes a blink of an eye to transfer files. I guess data is only as good as what you do with it and other than the odd game download most the software is on floppy so your never going to be stumped for useful goodies on the Amiga.
Have fun.
PS: Wouldnt the train station software be linked to some data terminal where the operators input the actual train information. May have been also some kind of telephone link. Without the train network how is that going to work? Dunno.
All else fails just get some good floppies. Most of the Amiga software was designed in floppy sized chunks, particularly on the Amiga.
You could also set up a Parnet link. Slow, but effective.
And don`t forget the humble modem.