The fare finder has now been enhanced with CRS codes for National Rail stations. Could you please add them for tube stations (with codes starting with Z) as well?
Does anyone actually use those codes? The fact that there are two separate codes for stations like Barking and Upminster seems to be a recipe for confusion.
Some (but not all) are used in the National Rail timetable and also ticket retailing systems, like ZEL for Elephant & Castle (Underground) and ZCM for Chesham.