The giant cockroaches that cover the surveillance camera lens at 71:47 on the DVD are not Computer Generated. Director Robert Shaye mentions in the commentary that the production employed three "cockroach wranglers" to handle the insects.
During the 2012 Savannah Film Festival, Robert Shaye held a Q&A session after a screening of the film. During the Q&A, he stated that he was not a fan of the film's title. He and other producers came up with a new title, "The Gifted", but it was too late in the production process to change it.
When Noah first controls a spider at the beach house (at around 19 mins), director Robert Shaye mentions in the commentary that Visual Effects Supervisor Eric Durst "got hold of the special effects house in Australia that did all of the visual effects for Charlotte's Web (2006) - they happened to have the computer program for making spiders crawling on webs."
The theme song to the movie, "Hello (I Love You)" (not to be confused with the similarly-titled classic song by The Doors) is a rare one-off song by former Pink Floyd frontman Roger Waters, whose songs are usually part of concept albums. Waters worked with composer Howard Shore, so that the song's melody is a leitmotif in the film, as well as dovetailing well with the rest of the film's score. Waters commented, "I think together we've come up with a song that captures the themes of the movie - the clash between humanity's best and worst instincts, and how a child's innocence can win the day." Incidentally, the film touches on themes that Waters' album 'Amused to Death' was concerned with, while the song's lyrics reference Waters' Pink Floyd works 'Dark Side of the Moon' and 'The Wall', as well as Waters' solo album 'Radio KAOS'.
The Hills Have Eyes II was accidentally shown in a theater session of The Last Mimzy (2007) in Holtsville, Long Island back in April 2007. The audience members were mostly made up of young children and their parents having to watch the graphic birth scene of the mutant baby at the start of the film. The theater employees were unaware of their mistake until they saw people running out of the theater room crying and screaming. The theater apologized and offered movie vouchers and free counseling services to all of the audience members of the misplaced film.