In the scene where Maciek is running away from Drewnowski and then the Russian soldiers, a train above them passes by. In one shot it is going to the left of the screen. Then in the next shot it is going to the right, then to the left again.
Glasses of vodka are set alight which burn for an unnaturally long length of time and with a bigger flame than expected, suggesting a purer fuel was used in the film, such as petrol. Moreover, when the final flame dies (c.41 minutes) no liquid remains in the glass. Only the alcohol content is flammable in any glass of spirit and a residue of water would be left behind with even the very strongest of Polish vodkas.