Adding provinces from Update Province Data doesn't add the provinces, just says ERROR. Example province from the editor program attached
EDIT: the provinces show up fine on the editor program though
EDIT2: I've updated, uninstalled, reinstalled, still same problem
EDIT3: Managed to get it to work in a roundabout way:
Step 1: Load up a different map, and exit the game with that.
Step 2: Change the NumberOfProvinces value to however many provinces you will have after adding the new ones (remember, provinces start at zero so the NumberOfProvinces = biggest ID number + 1)
Step 3: Make sure the files are all available in the template\update folder, numbered with their province ID
Step 4: Launch the game, head into map editor and load the map you're trying to edit. It should say something along the lines of "Generating province data" and the provinces will appear on the map.