A sign at the entrance to Elinor's house reads "Don't even think about entering"; underneath there are translated versions. Despite the novel the movie bases on is of German origin, the German translation on Elinor's sign is wrong - "Denk sogar nicht daran..." instead of "Denk nicht einmal daran...". (In the German dubbed cinema version of this movie, there is a voice-over while the sign is on screen, telling the correctly translated version.)
As well as the German, the Italian and the French on the multilingual sign are also wrong. The Italian says "non ci penso" ("I am not thinking") instead of "non ci pensare" ("don't think"), and the French has "gaspillar" for the correct "gaspiller" ("waste, squander").
The Volkswagen Campervan that is used near the beginning of the film has a Zürich number plate, yet the cantonal coat of arms to the right of the number plate is that of the canton of Ticino (red and blue stripe). This is incorrect: The coat of arms should have been a white-blue stripe, which is the coat of arms of Zürich Canton and would correspond correctly to the number plate. Besides, the number plate shows seven digits, whereas number plates in Switzerland have a maximum of six digits.
Mo has been looking for a copy of the book for nine years and apparently never thought of contacting the author until his daughter mentions it. We don't know what he did during the nine years. He might have tried to contact Fengolio but failed. He may have thought that his story was too hard to believe - who would believe that his wife was trapped inside the book? He may have saved it as a "last resort" item in case he never found a copy for that reason. Then, during the time-frame of the movie, he decided to try it because he had proof (Dustfinger) and it was an emergency.