When Duck and Roger are discussing Duck's potential partnership, the position of his cigarette pack on Roger's desk changes between shots.
This series is set in 1962. The Mercedes Benz sports (body W113) that Don gets into with Joy wasn't released until mid 1963.
Set in late 1962, during nuclear weapons presentation a USSR map is being demonstrated where Stalinrgad can be seen. But this city was renamed to Volgograd in November 1961.