In Chapter Three - The Benediction, a 1970 Chevelle Malibu 4-door sedan is used in several scenes (rear bumper with square taillights), and the car which is totalled before the segment ends is a 1972 model (rear bumper with 4 round taillights). The 1970 Chevelle used in the film has a front grille from a 1972 model, headlights from a 1971/72 (1970 Chevelles had 4 headlights up front), and turn signal lenses from a 1971.
Episode: Bishop of Battle
When J. J. Cooney starts playing the head arcade game, a scene shows his score raising from 380 to 470 points. As he progresses in the game, another scene shows his score raising from 1740 to 1830 points. However, when J. J. reaches level 13, the scene shows his score at just 100 points. A few scenes later, we can see his (presumably normal) score raising from 10390 to 10510 points. At this point, however, the highest score of 89462 points looks quite hard to be beaten.
Presumably as the Bishop of Battle game progresses, the view/angle of each level changes to make it more difficult for the player. We see this the first time JJ plays the game as level 12 is at a lower angle and shows less of the overall play arena than level 11 had. However, the second time JJ gets to level 12, the angle is now almost a first person shooter, with the player's view being from the ground rather than an aerial view showing their player character.
In "The Benediction," just after the demon truck leaps out of the ground and begins to chase Frank again, the shooting lights on the camera tracking truck are reflected on the side of Frank's car and are clearly visible for several seconds, despite the brightness of the day.
When Father MacLeod is saying the funeral Mass for the slain child, the Latin he uses is completely random. For example, during the ablutions (where he is washing his fingers presumably prior to the consecration) he is saying the "Hail Mary", which is not part of the Mass liturgy at all. Also, if the action is contemporary (as the cars being used suggest), the Mass would almost certainly be in the vernacular (i.e. either English or Spanish).