Factual error: Brod railway station is not (and never was) an isolated railway station with mountains behind it. No mountains are visible from it but the town and fortress are nearby and easily visible from the station.
Continuity mistake: Poirot is reading A Tale of Two Cities, at a table with a cup of coffee. Johnny Depp comes over and puts some cake down. Shortly afterwards a jug and a glass of water appear on the table from nowhere and remain there for the rest of the scene.
Question: In the opening scenes when Poirot confronts the rabbi, priest, and imam - the priest is Catholic / Western Rite. But from the setting of their dispute in Jerusalem, shouldn't the priest be Orthodox / Eastern Rite?