For the scenes where Ruby suddenly speaks French, in the French language dub it is changed to her suddenly speaking Italian.
This idea was explored in the TWILIGHT ZONE episode "A World of His Own" and a Steven King story, "Word Processor of the Gods."
The eccentric house that Calvin's mother Gertrude in which lives is supposed to be in Big Sur, but it is actually a house in the Hollywood Hills that once belonged to Sid Krofft. Much of the dialogue in that scene describing material details about the house was written on the spot based on the actual owner's tour of the place on the day of the shoot.