I'm gonna say the top picture was mounted to a trunk or piece of furniture, that had a lock on it. The round hole would have been over the lock, thus the picture of the key underneath.
The second 2 I think are buttons.
The 3rd, (w/race car) looks like the face of a pocket watch.
The cast iron looks like molds for "wood like" shingles, that would have been made of clay.
Regardless whether I'm right or wrong, they are all very cool looking pieces!!