Stuart OK? Been upset for old movie comedian? (6,6)

I believe the answer is:
'old movie comedian?' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'stuart ok? been upset' is the wordplay.
'upset' is an anagram indicator.
'stuart'+'ok'+'been'='stuartokbeen'
'stuartokbeen' is an anagram of 'BUSTER KEATON'.
'for' is the link.
Can you help me to learn more?
(Other definitions for buster keaton that I've seen before include "Broken statue (anag) - early film star", "Silent screen star", "Silent film comedy star, d. 1966", "US actor/director", "Comic".)
I've seen this clue in Sydney Morning Herald.