I'm having the same issue as of yesterday afternoon. I've played about 40 hours.

Came home after playing in the morning and got this in the application event log

The program Kingmaker.exe version 2018.1.0.55711 stopped interacting with Windows and was closed. To see if more information about the problem is available, check the problem history in the Security and Maintenance control panel.
Process ID: 2618
Start Time: 01d468be31ac7a1c
Termination Time: 1
Application Path: C:\Program Files (x86)\GOG Galaxy\Games\Pathfinder Kingmaker\Kingmaker.exe
Report Id: 795dea3e-8f31-480a-bf60-a25fb81bb35a
Faulting package full name:
Faulting package-relative application ID:

This is fresh install of Windows as of a week ago, minimum of stuff installed. Nothing has changed on my PC since I left, I checked the logs and the PC went to sleep for most of the time I was out.

To date I have:
- Rebooted
- Forced it to run as Admin
- Redownloaded Pathfinder
- Removed my save files
- Disabled GoG cloud saves and overlay
- Disabled A/V
- Disabled Smart Screens
- Deleted the Owlcat folder in my user profile
- Checked all the drivers are up to date
- Installed DirectX as per GoG support suggestions
- Someone mentioned Citrix issues with Unity, I don't have any Citrix apps installed
- Deleted the registry key
- I can run the game, over the network, on my wife's PC!

This is definitely something on my PC but I can't figure out what it is :(

Uninstall the game. Uninstall Galaxy. Re-download Galaxy and install it OUTSIDE of Program Files(x86). You should NEVER install games in that Windows protected folder. Install Galaxy to a base drive -- C:\GOG Galaxy, for example.

This might or might not be the cause of your issue, but something is making Kingmaker hang -- that's what "stopped interacting with Windows" means -- and Windows protected folders cause all sorts of issues for games. Ensure the drive and folder you install it to has full administrative permissions.

Remove any non-essential devices and peripherals also.