Other mistake: When Vera returns to her house, a calendar with 2017 listed as the year can be seen on the wall. The present-day scenes take place in 2014, so there shouldn't be any reason for anyone to have a 2017 calendar. (00:56:55)
Other mistake: Vera goes into the attic and finds a computer. She opens the web browser, but when she begins to start typing, we can see that the search bar already has text typed into it. (00:57:17)
Other mistake: When Vera finds the Mirage book in the library, the publication year for that print of the book is listed as 2017, but the movie takes place in 2014. (01:10:38)
Other mistake: When Clara pulls the knife out of Hilda after stabbing her, in the shot of Hilda falling over the staircase, no blood can be seen on the knife. But every other time the knife is shown, there is blood on it. (01:30:53)