Just updated my map to version 1810 and had to select map 2 due to size, which as highly unlikely to go to any of the countries omitted or actually any other country than UK, was fine to do.
Achieved this on Chromebook also, as both windows laptops in this house are company encrypted.
Was pretty simple, downloaded the zip, unzipped it with an App called RAR, backed up the existing map, and then deleted it off the SD Card, and replaced it with the extracted map version. Never bothered in my GTD or R, so first time done it and was expecting more issues especially on a Chromebook, but thankfully fears unfounded.
Reason did this, was due to driving out to Clacton yesterday and whole new bypass had my Sat Nav panicking that I was going off piste and into some fields.