The comment early in the movie about the cat and buttering its paws comes from a technique used when a cat moves houses. According to this, if the cat has butter on its paws it will stop and lick it off. As cats are very clean creatures, the butter on its paws and the bits of dirt/dust/debris that will inevitably stick to it will annoy the cat. The cat will sit down to clean itself and, in doing so, will take in its new surroundings creating a mental map of where its new home is and helping it to make the adjustment to its new surroundings.
Director Sir David Lean insisted on using three-strip Technicolor film despite it being difficult and costly to obtain in wartime Britain. In doing so, he was obligated to have a Technicolor consultant on the set to ensure everything was photographed correctly to Technicolor's standards. Lean was annoyed by their interference and mainly ignored them, hence this film does not have the look typical of a Technicolor film from that era.
On 20 January 1936, Frank and Ethel listen to Stuart Hibberd's BBC wireless broadcast about the impending death of King George V - "The King's life is moving peacefully towards its close."