While Anna and Lady Mary are talking in Lady Mary's room (min 11-12) the flower pattern on Lady Mary's nightgown pokes out of, then back into her robe.
During a long shot at the beginning when Lord Grantham, Lady Edith, and Lady Mary are having breakfast, the tablecloth is off center on the table; the right side is down lower than the left. In a subsequent long shot, the tablecloth has been centered with the left and right sides even.