I've gotten to Fulgora and completed the initial wall, while trying to create new connections rather than use the previous loop design for the electric network. So far, the issue has not reproduced, but I would still like to know what caused it in the first place.

To confirm, the game still crashes ...

Fascinatingly, I just learned about the Map Editor, and when I tried to convert the Save into something that I could edit, it ALSO crashed Factorio! I'm intensely curious as to what I did that could cause this behavior...

It can load fine, it can play fine, but you can't save in the map and you can ...

I noticed the post got updated to include the ElectricSubNetwork in the title, due to the error in the log file (I presume).

That said, is there a specific section of my electric network that is causing the problem? If so, I can delete that section of it, just so I can keep building the rest of the ...

Current Behavior: Autosave and Save both crash the game every time
Expected Result: Autosave and Save both save the game and I can continue playing as normal

Steps to Repeat:
1) Load Autosave1, Autosave2, or Autosave3 (attached)
2) Save the Game
OR
3) Wait until Autosave tries to save the game ...