After some investigation, I found (so far) that game optimized poorly and mostly crashes on PC with NVIDIA graphics cards and Windows with x64 architecture. If game runs on WoW64 (it will), it caused to accessing to some memory addresses that crashes game. Most of known solutions don't fix the problem completely. Reducing zombies count, entities (physical, movable), particle emitters or models variety also does not fix the problem.

You can make it as virtual machine (use only VMware Workstation Pro[drive.google.com])
1. Install Windows x86 (32bit) (most of problems when FZ working on x64)
2. Install Steam, redistributable stuff[drive.google.com], FZ

You cannot use Windows 11 for it, there is no 32bit version

Okay, that can be possible due to one specific video from here


1. Install VMware Workstation Pro[drive.google.com] (VirtualBox has not enough vram)
2. Make Windows 7 x86 (32bit) virtual machine (most of problems when FZ working on x64)
3. Set maximum of your videocard's capacity, 3072Mb RAM
4. Do everything from video above
5. Install Steam, redistributable stuff[drive.google.com], FZ

If main menu start glitchy -> try to start new game and return back or just make screenshot (press PRT SCR)

• FullScreen=false - windowed mode
  
• ScreenWidth=1080 - width in pixels
  
• ScreenHeight=720 - height in pixels

• Debug=true - enables Debug mode
  
• SessionLog=true - prints data to fzlevelcontentlog.txt (in game folder)
  
• VisualizeAI=true - shows zombie states
  
• ShowPlayerAnimationDiagnostics=true - draws player's animation state + route
  
• ZombiesEnabled=false - disable zombies
  
• SoundEnabled=true
  
• MouseVisible=true
  
• ResetAchievements=true
  
• XenParticlesEnabled=false - dont know
  
• ExtendedDebug=true - dont know
  
• ContentMount= (string) - dont know
  
• EditNavigation=true - dont know
  
• Level= (string) - not working
  
• AudioDir= (string)
  
• SaveGame= (string) - internal error without crashing
  
• AnimationReposePeriod= (double) - not working
  
• DrawDistanceModifier= (float) - not working / 1f by default
  
• IrisSceneType=Normal - dont know

There's couple more but it's not useful

To run it just make shortcut with this params: FortZombie.exe XenParticlesEnabled=false Debug=true SessionLog=true
or you can use FortZombieDebug[drive.google.com] file to run game. Just put it into game folder (near FortZombie.exe) and run it.

Don't press Validate Game Content -> game will crash immediately

You need to enable Debug mode first
This is quite simple menu that allows you to:

• Choose character, daytime, mission type and load specific chunk of map (main scroll). Don't try to load any _navgraph "map" -> game crashes immediately
  
• Choose fast preset (missions)

0. Unpack fz.gob file using 7zip at game folder (you'll get fz.gob folder), remove fz.gob file
1. Download Python 3.12+[www.python.org]
2. Download my XNB XML Editor[drive.google.com]
3. Open CMD in folder with script
4. Write down pip install -r -r.txt and wait till end
5. Write down py xnbeditor.cpython-312.pyc


Open .xnb files from FortZombie/fz.gob/Config
Make backup, edit, save, run game.
Game crashed? Restore from backup

Mod examples:
New Character Class[drive.google.com]

Do you remember these two trees on the right standing near the police station?


Open .xnb files from FortZombie/fz.gob/Levels using same XNB XML EDITOR

• TerrainModel - static model
  
• Model - model with physics
  
• ZombieWave - zombie spawner
  
• MaskedSpotLight
  
• Light
  
• Container - model with inventory
  
• ParticleEmitter - smoke, fire
  
• MissionBeacon
  
• SurvivorSpawnPoint
  
• BreakableSlab - window glass
  
• HingedDoor
  
• Building - prebuild map
  
• StartPoint - player spawner

It's also possible to change some textures in game
Mod example:
Custom UI Elements[drive.google.com]

Collision view -->
Ctrl + Alt + F2
Reset player position
Ctrl + Alt + F12
Change daytime (skybox, light)
Ctrl + Alt + T
Hide HUD
Ctrl + Alt + H
Run defence mission
Ctrl + Alt + D
Change camera
(free camera, behind shoulder, classic)
Ctrl + Alt + С or V
Spawn survivor
Ctrl + Alt + S
Spawn zombie
Ctrl + Alt + Z
Hide physical models
Ctrl + Alt + End
Noclip mode
Ctrl + Alt + F3
Lift player while noclip -->
Ctrl + Alt + Space
Top view
Ctrl + Alt + PageDown
Close view
Ctrl + Alt + PageUp

Do not use this hotkeys while main menu, game will crash

• Navigate to C:\Users\*username*\AppData\Local\Kerberos_Productions\FortZombie.exe_Url_***\1.0.7.0 (or use FortZombieData[drive.google.com])
  
• Find <RenderQuality> tag and make it as <RenderQuality>VeryHigh</RenderQuality>

Not sure if the quality will be better but it's an official option that not showing in list

I liked robocrush123's idea about FZ speedruns. Thanks to him about it.
And thanks to my guide it's possible now without game crashes.

Leaderboard: https://www.speedrun.com/Fort_Zombie_
WR