When Crystal comes down the stairs she has a black silk handkerchief in her hand. She then kneels on the side of the sofa and starts talking to someone with the black handkerchief still in her hand. After the end of the talk she tosses the black handkerchief away and it falls to the floor. Then when the camera cuts back to her it's back in her hand again.
After Ferguson serves drinks to the two at the piano, he leaves with three drinks on the tray, but then when he opens the kitchen door and sets the tray down on the table, there are only two drinks on the tray.