When Lawrence Olivier and Michael Caine are playing snooker, Olivier pots the black. There is then a wide shot, with the black visible again on its spot. The next shot is a close up of Olivier picking the black ball from the pocket and replacing it on the table.
Marguerite Wyke was "played" by Joanne Woodward, the wife of Paul Newman. Woodward's likeness was used for Andrew's painting of Marguerite, and the actress listed as playing her was a fictional name.