Other mistake: In the Italian dub, Egon mentions that he raised the room temperature to 42°, which would be almost 108 F, instead of the correct 95.
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: There's an unnatural jump-cut near the end of the movie, just before they shoot Vigo with the proton pack.
Other mistake: When the Ghostbusters are inside Lady Liberty, you can see from their close-ups and from shots inside the head that the windows that form the crown are narrower than their shoulders. Despite that, they easily make the drop on the villains from there, while carrying huge backpacks (the slime ones have large tanks even). (01:30:20)
Other mistake: Dana leaves her home in such a hurry that she does not even put anything on her baby in the middle of December. She shows up at Peter's home, he phones Ray who then rushes out of the door saying he's gonna check Dana's apartment. Peter tells Dana that Ray is going to check her apartment, but their phone convo ended way before Ray had taken that decision, and he has no contact with the others till morning when they meet at the museum.
Suggested correction: Dana easily could have grabbed something that was laying on a table or piece of furniture that was on her way as she was running out of her apartment to dress Oscar in, or a good Samaritan could have given something as she made her way to Venkman's place. And Ray tells Venkman on the phone that he is going to check Dana's apartment.
Other mistake: Ray obtained a small sample of slime through a very little device, a sphere smaller than his fist. The slime is brought back up in court as "exhibit F" and it is said to come directly from the trunk of their car; the sample is almost 1400 ml, way larger than it should be. (00:25:20 - 00:29:05)
