I think some of the confusion is when your credit wheel is in reset “0” credit position it does not show “0” in the credit box so you might think there are credits when there is not. Your pictures show the max credit switch open but I can still see your credit wheel max of “15” when your unit is at max “15” should be displayed in the credits on the backglass.
So here is what I would suggest,
1. Get the credit unit into the reset position.
2. Correct the alignment of the credit wheel to show “0” in the backglass.
3. Manually step/reset the unit and adjust the switches if need be.
I think once you do that until you close the minimum credit switch for free play anything above “0” for credits will start a game. I also attached one of your pictures that shows the max credit switch open and the reflection of the credit wheel so you can understand what I am saying.
Hope this helps.
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