Reseat both ends of that display cable, with power off. Also please post a picture the the MPU surrounding the battery holder. i hope there is no battery damage.

Can you flip both ends of the ribbon cable? So pin 1 of the ribbon cable will be at pin 26. This should rule out the cable for sure. Honestly, I would not mind seeing a video of this problem. Pinside only accepts links to videos from elsewhere. I do not know what you mean by "locks up at end of the programming". Do you mean once a game ends? Is the diagnostic LED still blinking when the display locks up?

What game ROM version is in it? It should show when you turn on the game. Can you go through the display test and let it run a couple of cycles?

What other games do you have?

It definitely is not a commonly seen issue. Seems like it has a problem resetting after exiting the adjustment menu. After turning on the game, can you add credits, start a game and play through a full game and it ends a game properly?

Not related to the adjustment menu or adjustment failure.

It is between the battery, RAM and some supporting logic.

I suggest having 6116 NVRAM installed if you are not able to solder. Removing batteries from this nice original board seems like a no brainer to me. ChrisHibler can install one for you.

I also suggest having the electrolytic capacitors replaced on the original power supply as their life has expired.

It will help...new NVRAM now has 123 year retention rate. Board will be totally protected. No more batteries to throw away. Those coin cells are made in China and usually only last 2-3 years. They do leak at some point once they begin to fail. I can't see why anyone wants to ever risk batteries of any type anymore these days. This also will benefit anyone else having the game after you.

Good thing about sending it off for repair to install the NVRAM is that if it does not solve the problem, it will get looked at.

Try this...Turn on the game with the door closed. Press this CPU reset switch in momentarily. Give it a few seconds for it reset. Now does it go into attract mode? Display went back to normal?
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It didn't change because the issue is not with the voltage to the display from the transformer. You should have measured the -100v and -98v at the power supply that ends up going to the display.

This is definitely an issue with the CPU board. It is quite possible the problem is with the original U25 RAM. Out of all the repairs I have done on System 11 games and issues reported with Adjustment failure, I never seen one act like yours. Step 1 would be to replace the U25 and then see what the result is.

That is great. Did you send the power supply with it to have the capacitors replaced, or you believe you can handle it? The electrolytic capacitors have only a certain lifespan.

Between that and NVRAM, your board set will be the most reliable it can be. Many less worries.