Don’t know about agent, but this user purchased the U.S. version and subsequently uninstalled it, followed by re-install from an S&N UK version download.
Thanks Charlie for the download link to S&N. I downloaded the 64bit UK version and (after uninstalling my US version) installed it onto my laptop. It just worked - didn’t even ask me for the username and key. Then I made a test tree and added a single person. I added an Association fact type and was surprised to see that the spelling of the word ‘neighbours’ was still in the American way - ‘neighbors’. So I too wonder what the difference is between the two versions.