Other mistake: Spock lifts his crew mates with the rocket boots. He passes deck numbers 35 through 78 from bottom to top. First off, deck numbers go from top to bottom. The bridge is on deck 1. Second, the Enterprise of that class only had 23 decks.
Other mistake: Beethoven didn't seem fussed nor resentful of Napoleon being part of the group. Historically he temporarily admired him and wrote the Third Symphony inspired by Napoleon's ideals of Europe's new hope of enlightenment but later despised him after he crowned himself Emperor of France in 1804 and furiously scribbled out his name off the title page of his Third Symphony and named it Eroica which he originally titled it as "Bonaparte Symphony" due to his former admiration of Napoleon.
Other mistake: When Doc, Marty and Jennifer have arrived in 2015 Doc tells them that the time of the day is 4:29pm. However the destination time is still shown on the time circuits' display from their time travel to the future - the two times should match, but the destination time has the bottom AM/PM light illuminated, while the current time has the top one lit. They didn't arrive or leave at 4:29am, so something's wrong somewhere. (00:04:42)
Other mistake: Near the beginning there is a scene where they are launching a submersible with Lindsey and the seal team in it. Lindsey waits until the sub is dangling over the water then pulls a lever and the sub drops about 10 feet into the water with a big splash. Several problems: 1) Those subs are hugely expensive. They put them in the water very gently. 2) Those subs are so expensive that they don't risk having a release mechanism as depicted. They use a standard screw shackle to ring and would have to have a swimmer let them go. 3) Due to the buoyancy of the sub, falling that far to the water would give all passengers back injuries due to the sudden deceleration when the sub hits the water.
Other mistake: When Dana enters the hall after being attacked by Pin Head, the door opens out into the hall, but it should open into the room, not out into the hallway. (00:57:00)
Other mistake: In the Italian dub, the kids at the birthday party vociferously ask for their hero; Tree Man instead of the original He-Man. He-Man was very popular in Italy too at the time, it was not an obscure reference that needed any adaptation - not that there is or was any character named Tree or Tri Man in Italian pop culture.
Other mistake: When Amy hits the button to tell her dad that breakfast is ready, he tries to type "I'll be down in five minutes." However, the message on the strip of paper says "I'll be down in five mimmicks." Amy says, "Typing with his gloves on again." Even if someone was typing with their gloves on, the blatant misspelling would not happen.
Suggested correction: They're on an emergency rescue mission and don't have time to be delicate with the equipment. Also, everyone in the sub is shown being thrown around when the sub hits the water. Hence the angry looks toward Lindsey.
They would still put the sub safely in the water. The first thing in priority in a rescue situation is scene and crew safety. If you damage the rescue sub or hurt the rescue team what's the point of the rescue. They would take the extra few minutes necessary to put the submersible safely in the water.