Does anyone remember the scene in which Marco (F. Murray) visits his aged parents?
Wasn't that Claire Bloom playing his mother? I could swear that his father was played by John Neville, who saved Vienna in Terry Gilliam's Adventures of Baron Munchhausen. It might have been him. He died many months before the release of the film, but production started months before his death. Anyway, the cast list doesn't tell us who played his parents.
Watched this on Netflix streaming and the credits that run at the end of the film bear little resemblance to what you find in IMDb. Marco's parents are referred to there by the names Rosa and Carlo Cristofori. Rosa was indeed played by Claire Bloom, though the father was played by Gianni Musy, who somewhat resembles John Neville and, coincidentally, also passed away in 2011. IMDb not only lists different actors for these roles, but the actors named are about 40 years old, give or take, while the actors you and I saw were about 80.
Are there two versions of this movie, with different actors in some places? This wouldn't explain the age discrepancy in the actors playing Marco's parents, unless they planned at some point (or maybe they actually did it in another version of the film) to show a scene with young Marco and his parents. Maybe the plan was to age them with makeup for the scene where the parents were older, but later dropped the scene requiring younger actors and just got older actors for the version we saw.
Very, very odd.