When the landslide occurs, the kitchen shakes violently (through camera motion). But as Libby runs through the house, the rest of the house isn't shaking at all.
When Libby and Barry are in the loft, Mrs. Saul comes to the barn. The Sun is setting and lighting the horizon behind the barn. As Mrs. Saul walks toward the barn (and the light) her shadow falls on the barn toward the Sun, not away from the Sun and toward the viewer.