In Marley Brant's 2006 book "Happier Days: Paramount Television's Classic Sitcoms 1974-1984," Robin Williams revealed that he didn't watch the movie, joking, "If they're going to make a bad movie about your life, you should wait for the Cartoon Network version."
Resident "Mork & Mindy" director Howard Storm was critical of the production but heavily praised Chris Diamantopoulos for his portrayal of Robin Williams.
In the scene at the club, where an NBC talent exec is there to see Jay Leno but finds Robin Williams instead, a quick shot is shown of someone 'playing' Jay Leno in his younger days. The actor is actually the winner of a "Jay Leno Look-alike" contest run in 2004 on The Tonight Show.
In the movie, they sold the show to ABC without a pilot by cobbling together footage of Robin Williams in My Favorite Orkan (1978) with Pam Dawber from a shampoo commercial. This did happen, but in reality they used footage of Dawber from the unsold pilot Sister Terri (1978).
Since they couldn't precisely replicate scenes from "Mork & Mindy," writer David Misch utilized rejected dialogue and gags that he'd penned for the series decades earlier.