Max CPU, 5 FPS, save suddenly became unplayable

Issue description

64 years into a playthrough without any problems, plus many other maps and saves without issue, this particular save/map (a slightly modified version of fer a chevre, https://hub.coigame.com/Map/Detail/273) seemed to have suddenly grenaded itself. CPU is pegged, FPS drops off a cliff (particularly at speed 3). I have a decent rig, and this has never happened before in any previous update or map.

System Information

  Time of this report: 4/11/2026, 03:32:04  
     Operating System: Windows 11 Pro 64-bit (10.0, Build 22631) (22621.ni_release.220506-1250)  
            Processor: AMD Ryzen 7 7800X3D 8-Core Processor            (16 CPUs), ~4.2GHz  
               Memory: 32768MB RAM  
  Available OS Memory: 31850MB RAM  
            Page File: 38448MB used, 5210MB available  
      DirectX Version: DirectX 12  
     User DPI Setting: 96 DPI (100 percent)  
   System DPI Setting: 288 DPI (300 percent)

Reproduction steps

Save: broken.save

Do you need the map as well? or does the map get baked into the save? I'll attach the map as well.

my chevre.map

Game version and build number

v0.8.2c b559

Operating system

Windows

RTX 4070, again, never ever had a performance problem with the game before. OS and game drive are both SSDs.

It seems to have settled down -- I'm guessing some calculations involving vehicle pathing or mountain settling of very tall mountains cleared up.