Other mistake: The reporting of the horse race used to sting Doyle Lonnegan stops as soon as the fake FBI agents raid the bookmakers. J J Singleton, who is reading the results of the race, stops when he sees the raid taking place. However, that was supposed to be a live broadcast from the racetrack itself. It should have continued. Lonnegan isn't stupid - he would pick up on something like that immediately.
Other mistake: In the race scene between Milner and Falfa, you can see exhaust smoke coming from Milner's car, but in a previous scene the station attendant mentioned Milner taking the header plugs off. By taking the header plugs off, his exhaust is running from the headers and you wouldn't see exhaust coming from the tail pipes. (01:03:15)
Other mistake: Dunnaway fires a warning shot next to her father to encourage him to leave the property. In the sequence just before he leaves she fires one shot and there are two dirt eruptions near his legs.
Other mistake: When the family first enters the chalet, you can see the curtain move to the left of the door as they all pass by it, indicating that the window to their chalet is the one to the left of the door. In the next shot, it shows that there is a solid wall to the left of the door, and the window to their chalet is actually to the right of the door.
Suggested correction: This isn't a mistake. The person "operating the radio" could easily have switched it off because of the commotion. Lonnegan would simply suppose this is what had happened. He is not going to instantly suspect someone is faking the whole thing.