Too many connections goes to "?"

I couldn’t figure out why at some point the file stopped being able to converge on a solution, but upon testing adding/deleting connections I’m fairly sure it is based on a limitation on the program to handle a certain number of connections. The file I’m uploading is stable, but when you add 1-2 more connections (regardless of outposts or even splurgers) it will go to “?” that will never converge on a solution. You can test this file on anything, but I’ve specifically tuned it to fail as soon as you add one more beam, pipe, or concrete connection which all should be pretty light mathematically.

I am a very novice-level amateur programmer so I’m not sure what exactly is the issue, but I suspect the algorithm get caught in a local minima because it’s trying to calculate too much at one time. The rest of the connections are much more complicated than this one so it should likely be simple addition for these connections.