@Uhtred - Try deleting that travelDB file and see if that works. You shouldn't need the travelDB file. Only the nhd file is important. You can open IP normally in your game and save immediately. Then copy in that nhd file to overwrite the other that was created. Then save as your new template.
This save was created on an older version of the game; so maybe if you have the latest game update, it somehow changes the way that worked before.
Please let me know if deleting the travelDB file works or if saving a fresh game in IP and replacing the new .nhd file with mine will work.