When Chuck takes the scarf from Grace's neck it shows up two shots later, then is gone again in next shot.
Jack refers to the steeple casting a shadow which touches the O of the store's open sign at exactly 5 PM each day. This would actually only occur on a few days each year, as the lengths and positions of shadows are constantly changing through the seasons.
Many continuity issues (hats on/off in alternating shots etc) are entirely deliberate. There are a large number of quick cuts throughout the film which serve to disorientate and confuse the viewer. The continuity in these cases is never precise and is as much a part of the final film as the script.
When Chuck first rapes Grace, her head is "inside the wall" in one shot.
When Jack McKay admits that he is blind, he says "In Switzerland they call it the Alpengulen." It's in fact called Alpenglühen.