Errores

Sophie takes a bottle of wine with her left hand, and the next shot shows her taking it with her right hand.

When Sophie and Ethan are in the attic the naughts and crosses grid changes several times with the final naught in the top left corner eventually changing to a cross.

While Ethan is on the phone, there are several shots showing the door open in the background (in an adjacent room). In the penultimate shot, the door is almost fully closed - then open again in the last shot.