Anyone know how to translate locations codes such as: 2520, 3318 / 3317, 725 into a place/train/station?

Try this:

http://www.post.ch/db/owa/pv_plz_pac...?p_language=de

And this link, has the data in txt format in case you wanna do something fancy with it:

https://match.postmail.ch/downloadCenter?product=2

As alluded to by the links, the SBB uses postcodes....kind of 'logical' ....

Do you know you can put the postcode of where you want to go into the keypad of the blue ticket machines in Zurich, and it will give you the ticket you want ? Very clever....