Build your factory as a Spidertron from the start! Instead of unlocking better weapons and armor, unlock upgrades to yourself.
Mods introducing new content into the game.
Transportation of the player, be it vehicles or teleporters.
New ways to deal with enemies, be it attack or defense.
Here's a version of the function that made the problem go away.
I'm curious, what mods were you using to make it crash?
It could be a number of different things; I didn't bother checking further after finding out something that made it stop crashing. It's possible that it's train construction site?
