Thank you! 😀
(I edited out a whole bunch of tangents and digressions from this - but I think the core of it is still there...)

Thanks Meinert! 😊

Before VHS tapes I had Vonda McIntyre's novelisation to 'rewatch' the story. It was based on the original script and included more of Preston; I was delighted to finally see the scenes which I'd only read about! It makes Scotty's grief in sickbay more understandable - worth the character moment?
🖖

Also worth mentioning is producer Harve Bennett's DVD interview when he compared the reactions of test audiences to the original, funereal cut with the revised version. He gets a little teary-eyed as he describes how it felt to give the audience a sense of hope again.

Irish Free State was established in Dec 1922; Mongolian People's Republic was established in 1924 but isn't shown yet indicating the map must be from 1923.
But: Central Australia existed from 1927 onwards. So I assume the map was made shortly after 1927 by a cartographer who hadn't kept up to date?