Trivia: At the beginning of the movie Kirk rescues McCoy from a jail of some sort. Before leaving Kirk asks McCoy how many fingers he's holding up and does the Vulcan hand thing. However, Shatner had severe difficulties putting his fingers into place, they just wouldn't hold into position. So the crew wound up wrapping fishing line around Shatner's fingers, he would put them into position out of the camera and the shot quickly jumped while his fingers where still in place. If you look closely you see the line around his fingers. (Note that this problem occurred several times during Star Trek, actually, Nimoy and Leonard seem to be the only people doing this without a problem.)
Trivia: On the backside of the DVD near the bottom is a series of six images purportedly from the movie. The second image shows the crew in uniform, including Mr. Spock, standing in the Federation Council chamber. This image comes from the movie Star Trek IV: The Voyage Home (after the crew has returned to Earth and is waiting to hear the Council's judgment).
Trivia: Robin Curtis replaced Kirstie Alley as Lt. Saavik in this film as Alley, who had starred as Saavik in "The Wrath of Khan", was offered less money to reprise her role so turned it down.
Trivia: The voice on the flight recorder is that of the film's producer, Harve Bennett.
Trivia: The first time we hear of "transwarp drive" technology is in The Search for Spock; presumably, using Transwarp Drive, the Excelsior should be able to easily overtake the Enterprise, even at maximum warp. Montgomery Scott easily sabotages the Excelsior, however, and we never see the transwarp drive in action. For some reason not explained in Star Trek canon, the Great Transwarp Experiment was abandoned as a failure at this point, so we never learn of the actual maximum speed of a starship with Transwarp Drive.
Trivia: Leonard Nimoy does the turbolift voice in the scene when Scotty says "Up your shaft", whilst exiting the Starship Execelsior. The end credits lists the voice under the alias Frank Force.
Trivia: Spock's coffin is a photon torpedo capsule with "Mark VI" written on the top. Mark VI is the chapter in the Bible which relates the raising of John the Baptist from the dead.
Trivia: In the film, Cathie Shirriff plays a Klingon named Valkrys who appears to have had some sort of relationship with Commander Kruge (Christopher Lloyd). In an episode of "Taxi," Shirriff played an old flame of Lloyd, Jim Ignatowski.
Chosen answer: Kruge only had the proposal video that talked about what Genesis was. He didn't have any actual data on how Genesis works or how it could be created. Having footage of a nuclear blast doesn't give you knowledge about how to build a nuclear device.