Actress Colleen Camp who previously portrayed Rita's Mother doesn't appear in this movie. The character is apparently killed in an unseen spelunking accident. Camp was apparently difficult to work with and was written out of all future SSD movies at the main casts request.
Actress Carol Burnett who portrays Norman's Grandmother in previous movies was unable to appear in person in this movie and is only seen on computer screens. This was due to scheduling conflicts arising from the CBS Carol Burnett Special that needed re-shoots after Kevin Spacey was removed from the broadcast.
When this movie was filmed the cast and crew believed it was going to be the final SSD movie made. When filming was over the sets were completely dismantled and cast members took mementos home. Kristin Booth took home Shane's necklace and almost couldn't find it when preparing for the next film. The engagement ring Oliver gave Shane was also lost and in future movies they used Kristin's own real life wedding and engagement rings instead.
800 miles south of New Guinea is part of Australia, specifically the northernmost parts of Queensland and the Torres Strait Islands.