After the latest Win 11 update got applied, mostly all of 2D classics on GOG is no longer working properly. Either you have super choppy rendering, wrong colors or simply crashing. They did something to the rendering, unknown what. On my PC, i have previously working games now no longer working (Tzar, Runaway, Rage Of Mages etc). This is catastrophic for older 2D Windows games on GOG as it seems to be an OS thing affecting everything.

I was experiencing issues with Tzar before the last update. Interestingly, 7th Legion began working again on my main PC, which has an Intel CPU. Previously, it only functioned on my older gaming laptop that using an AMD CPU.

Rage of magic aways run great for me on 11, but I'll try it again.

Which update?
A recent one or back in the year 2024?
Have you tried restarting pc and not the shut down method?

This, perhaps? https://www.ghacks.net/2024/12/19/microsoft-confirms-auto-hdr-bug-in-windows-11-and-blocks-updates-as-a-consequence/

*IT crowd music plays*

Hm. One of the many times where I, having abandoned Windows, do offer nothing but scorn and a derisive snort.

I'm using the propitary NVIDIA drivers, no less!

Not only 2D games, but apparently e.g. Demonicon stopped working with Windows 11 update 2H24.

https://www.gog.com/forum/general/demonicon_wont_launch/page1

And no disabling HDR or auto-HDR doesn't fix that (I don't even have HDR enabled on the affected PC because the monitor does not support it.)

Also many newer games seem to be affected, also on Steam, e.g. Path of Exile 2 and many Assassin's Creed games (albeit some of these may have received fixes of their own already, at least many AC games).