Corrected entry: That knight in the temple of the grail - how does he know contemporary English after spending centuries in that cave? He's only alive because of the water - he's not imbued with mystical futuristic knowledge. A Medieval English knight (assuming he even is English, since Crusaders came from all over Europe) would be speaking either Old French or Middle English, neither of which would make any sense to the modern ear; they'd both sound like foreign languages.
Corrected entry: When Indiana Jones is escaping with his father and he sets off a boat as a decoy, there is no large crate on the dock. But a few minutes later, when the Germans show up, as they start going towards the boats, a large crate has suddenly appeared on the dock, from which Indy and his dad emerged on a motorbike.
Corrected entry: When the operators try to shoot Indy and his father as they rotate back into the burning room, the bullets flying towards and ricocheting off the rotating wall are evidently tracer bullets. Normally, tracer bullets are not normally issued for handguns; they are used more for rifles and machine guns.
Corrected entry: When Indy makes a rubbing of the knights' shield in the tomb under the library, he dives underwater with it. This would ruin the paper and make it unreadable, yet we see him later with it and it's perfect. There's no way he had time to seal it in a water-tight container before he dived.
Corrected entry: When Indy and Elsa are back at the hotel after the boat accident, Elsa's room is wrecked. How did Indy not know she wrecked it herself or hear her wrecking it? He was only 2 doors down. He could hear the music playing in the bathroom but not her trashing her own room. He should have known she did it when she came out the bathroom surprised. Seriously, how can you be in the bathroom and not hear someone trashing your hotel room?
Corrected entry: On the zeppelin, after Indy knocks the Nazi out, everyone stares at him in horror and confusion. He says to them, in plain English, "He didn't have a ticket" and EVERYONE on the zeppelin responds by getting out their tickets. The problem is, it's a German zeppelin leaving Berlin. Even if there were some people on board who knew English, it's highly unlikely that everybody on board would.