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.
Continuity mistake: When the slime is covering the museum an aerial view shows its surroundings empty. At the end of the movie, thousands of people gather around the place, yet the aerial view when the (superimposed) slime explodes is the earlier one, making it look as if the crowd had vanished, only to reappear a second later in close-ups. (01:37:50)
Continuity mistake: When the ghostbusters are yelling at the jar filled with plasma, on the close-up Venkman's hand is around a metal thing, but on the wide angles it is just by its side. This keeps changing back and forth. (00:39:20)
Continuity mistake: During the dancing toaster scene, the pool balls' position differ depending on if the wide or close angle focuses. (00:41:25)
Continuity mistake: When the Judge states his sentence, from Stantz's POV of the front of the table the pink goo in the jar starts bubbling with a tag hanging on its right side. From a wider angle of the front of the table not only is the tag not visible, but the ghost trap next to it is different (check the number of dials and looks of the box), plus the trap is now slightly skewed as to how it was positioned before. (00:31:45)
Suggested correction: I believe the tag is visible at all times, at least the string of it (the tag itself in the wider angle from the defence's table is hidden by the jar itself). Not sure about the mentioned box, you mean the ghost trap? My impression is that the different angle accounts for a perceived different placement, but it's just my perception.
Revealing mistake: When the [superimposed] pink slime and the bending tub try to attack Dana and Oscar, watch the tiles on the wall in front and you'll notice that they're not being reflected, just an empty space.
Continuity mistake: When the movie ends, Ray and Egon walk down the museum steps hugging each other. When the angle changes they are way apart from each other. (01:39:45)
Revealing mistake: When Oscar is standing backwards on the ledge, he moves frame by frame like a robot, revealing it's a stop motion effect and not a real baby. (01:15:00)
Continuity mistake: There's a scene where Spengler talking to Ray about Iran running Vigo The Carpathian through the Occult Reference Net. We first see the computer screen from the side, with Spengler and Ray looking at it, and in the next screen we see the screen head on. The layout of text on the screen, the books piled to the right and the shadow on the wall to the left are all different between scenes. The close-up of the screen is obviously a different set-up, close but not right.
Continuity mistake: The Ghostbusters pick up the 'symbol' for their fight by looking at the license plate of their Ecto 1A, which sports in close-up the Statue of Liberty right between the O and the 1. Problem is, in the rest of the movie, and that includes just a few shots before when they were blasting the jelly shell with their protons, Lady Liberty is to the left of the plate, before the E. (01:26:15)
Continuity mistake: When Hardenmeyer is escorted away from the room, the Mayor points his finger at a staffer and tells them to get the Ghostbusters. Another staff member calls his attention, but in that shot we see David Margulies through the window, and he is in a completely different position. (01:22:10)
Continuity mistake: When Peter tells Ray to hose Lucasz, Dan Aykroyd's hand is below and then above the slime gun in the two separate shots. (01:32:15)
Continuity mistake: When the Ghostbusters approach the giant uterine slime cocoon to try to breach into the museum, there's a group of firemen to the right. The late arrival to this group brings an axe. Cut to a wide shot and the guy is not carrying the axe anymore. (01:24:05)
Continuity mistake: Janosz is kinda bored as he awaits for the word of Vigo, the scourge of Carpathia. In close-up as he hears "I, Vigo..." he grimaces with his hands at chest height and not any wider than the shoulders. Turning to the wide shot, he is listening with his hands raised and the arms spread. (01:12:25)
Continuity mistake: When Dana tries to take Oscar back from the museum on her own, the cloth on top of the pillow where Oscar is resting goes from crumpled to straight. (01:18:20)
Continuity mistake: Tully is chasing Janine after she wished him goodnight. When the camera cuts closer to them, the cars parked on the sidewalk change abruptly, and they get back to the same models only at the end of the scene when someone honks a horn at him and the camera switches back to the original angle. (00:55:35)
Continuity mistake: While Peter is doing his pantomime with Vigo's painting saying "Walk for me talk for me, yeah!" you can see Dan Aykroyd stiffening on the ladder, acting as if Ray suddenly got possessed/mesmerized by Vigo. In the close-up that follows we see the process happening in a different and more gradual way. (00:51:40)
Continuity mistake: Janosz interrupts Dana and Peter talking about the Gaugain; behind him there are a man and an elderly lady passing by. Cut to Sigourney Weaver, and in the next shot the two people practically haven't moved. (00:43:10)
Continuity mistake: When Ray screams at the slime that "YooOOOuuUUU take the cake" his wrists in the background are crossed and the watch is visible. Cut, and his hands are joined and the wristwatch concealed. (00:39:45)
Continuity mistake: When Peter crawling like a worm draws the attention of the scourge of Carpathia that is holding the baby, shouting "Not so fast, Vigo!", notice Vigo's hair moving from the back of the right shoulder to the front. The hair changes position going in front of both shoulders to various° in the rest of the conversation. (01:34:55)