In the first flashback in Poland. A short fight breaks out between young Piotrek and his Father. His glasses get knocked to the floor but he picks them up and puts them back on. In the following scene one glass appears cracked. When the scene continues a little later in time his glasses appear perfect. Now it is possible that he had two sets of glasses but this would be unlikely in those times of hardship.
Going by taxi from Gare Montparnasse to Gare de l'Est in Paris, Abraham passes near Porte St-Martin which is north of the Seine and near Gare de l'Est before going near Notre-Dame which is closer to Montparnasse.