In the staircase chase, Cornelia runs behind David from the first floor (abbreviated on a sign as "1. OG") down to the ground floor ("EG"). However, in the next shot David is again on the first floor.
When David crashes in Cornelia in the first scene, he changes his position between shots.
The book that David gives to Cornelia when both are on the floor changes between shots.
When David gets up from the floor in the book magazine, a small light can briefly be seen between the bookshelves.