As Lucy Harker walks into the town square, she passes a 1970s single strut town bench concreted into the cobbles, and double yellow lines (no parking). When Lucy Harker shuts the front door of her house, there is a yale lock on it.
When Jonathan Harker first sets out on his trip, you can see in the distance, through the arch of bridge, the wheels and wings of motor cars parked in a herring-bone fashion on the opposite side of the canal.
When the captain of the ship is writing in his log he says they left the Caspian Sea, which is landlocked and nearly 1000 miles away from the port in Bulgaria where the voyage started. Bulgaria is on the Black Sea.
It is obvious that it is unbearable for Dracula to see a Christian cross. When he arrives in Wismar by boat, he brings a coffin to a church. On his way, he walks over a cemetery full of crosses, which do not seem to hurt him at all. In the church however, he is hurt by the crosses hanging there.
Though everyone on the ship dies during its voyage with Dracula aboard, including its captain, it still manages to miraculously reach its intended destination, the very town in which Lucy and Jonathan live. Even assuming Dracula was a competent navigator, the ship would be left to wander aimlessly through the daylight hours, rendering it completely unfeasible that it could arrive before Jonathan.
When Dracula breaks in on Lucy Harker at night and talks to her, you can see the tips of his fingers being reflected in the mirror, as well as his face in the top right-hand corner, until Lucy moves in front of it. Later on, Lucy reads that vampires do not have a reflection.
When Harker rides his horse to the Count's town, his horse has a white bandage on its left front leg that appears and disappears repeatedly from one shot to the next. Although the journey to the town took 4 weeks to complete, it is highly unlikely that the horse would get injured, heal, and then get injured in the same spot again. Apparently two different horses were used.