I am rediscovering a Western Hero machine I purchased almost 20 years ago. It has been in storage for more then ten years and I am cleaning it up and trying to give it a play again. I have a bunch of questions and I hope you all could help.

Pictures for reference
https://imgur.com/a/JYE8zps

1) What do the yellow and red buttons do on the front by the ball tray (1 in the picture)

2) On the ball field, there are 4 lights with a small digital display in the middle. During play I have seen the lights come on and the display show 0, 7, and 8. What do these signify ?

3) (3 in the picture) There appear to be individual lights for bullets for the play area at the bottom, but I have never seen them lit. Are these just for looks or do they do something?

4) On the back (4 in the picture) there is a small display that I assume will show error codes, is there a table if I see and error to find out what it means?

5) On the back (5 in the picture) There is a small pin that is connected to an arm that connects inside the machine, if you push it down, a single ball will pop out to the button tray. Eventually the machine actuates this pin/arm up back into its original position. I have found that balls end up in the track for this pin/arm by entering via the USA star and sheriffs badge on the front. What does this do?

I would also appreciate any additional information I might not be asking about related to how to play or how to maintain it in operation.

Thanks