Corrected entry: Shortly after the beginning of the movie, there is an establishing exterior shot of the town with a railway cutting, showing a single rail line. A steam train travels towards us, belching black smoke. Cut to Sofi in her workshop and we see the smoke from the train travel across the window from left to right, which means Sofi's workshop must be on the left hand side of the screen in the establishing shot. As she works on the hat, another train goes by, but this time the smoke travels from right to left. Remember, there is only one railway track. Cut back to exterior shot to see the train once again coming towards us, so either the smoke or the train are going the wrong way.
Corrected entry: When Sophie feeds part of her hair to Calcifer for strength, in one shot her hairband is still hanging on to her hair. In the next few shots her hairband is eaten by Calcifer, but when it cuts to Sophie her hairband drops off her own hair.
Correction: Sophie is wearing two identical headbands, one by her head, the other near the end of the long braid. Easily seen throughout the scene and before. Calcifer eats the braid, along with the headband at that end, but the hair has been cut below the near-head band.
Correction: The smoke outside the window moves exactly as it would if the train was moving right to left and the wind was blowing left to right.