For 5.1 and adding the The "Zippopotamus REST service allows you to retrieve location details based on a zip code. The service can be reached" it asks you to put in the Netherlands. I'd like to know after you follow the steps do you have to repeat them to add the countries you want or do the countries automatically come in if it's offered by zippo?
I guess the structure of the API call doesn't change for the 'new' countries. So the 'new' countries will be visible automatically when Zippo offers them.