The original play opened in Boston, Massachusetts, USA on 6 June 1927.
Maude Eburne was listed as a cast member in a contemporary Hollywood Reporter news item, but she did not appear in this movie. It's likely she was replaced by Lucile Gleason, as the character of Mrs. Peabody is very much in Eburne's wheelhouse.
The £5,000 Mr. Peabody pays for the necklace would be worth $21,186 at the time or approximately $390,000 in 2016.
The airplane depicted as being flown from Paris to London's Croydon airport is a Handley Page HP.45. First flown on December 30, 1931, this aircraft (G-AAXF) was owned and used by Imperial Airways and named "Helena". It was requisitioned by the RAF for use by 271 Squadron in May, 1940. It was scrapped after a landing accident in 1941. Only four were built.
According to a contemporary article in The Hollywood Reporter, Philip Merivale was considered for the male lead in this picture.