So this seems to be a plausible solution that seems to work. It works with all solutions and seems to leave 17 on the board between all the bits no matter what’s set initially. I didn’t try that many possibilities though so I can’t say for sure it works with every possibility. If someone understands how this translates into logical computations better then me that can see why it works or not mess up wants to confirm if it’s viable or not that would be cool. At this point I’m calling it solved even though I don’t know how to make a solution like one similar to the one in the book that I’m not trying to look at until I figure out how to make it on my own.

# Possible solution for puzzle 42 (37 pieces)

It looks like your overflow/underflow crossovers are in the wrong places - for example, if you start the left register at 8, the first blue ball will subtract 1 to leave 7, but be intercepted

I tried putting them on the opposite sides in the middle as well as both on the left and right, but this is the only method that seemed to work for all the solutions in the book… I also don’t know why they add to 17 whenever they finish. That might’ve just been a counting error on my part originally, but I’d have to open up the build and run through it again to double check