I remember wanting to run Heroes 5 at home on a GeForce 4 MX 440 video card... so, due to the shaders, the game refused to run on it. Out of curiosity, I decided to search the internet for a patch that completely removes these shaders... And to my surprise, I found one! And the game ran without any problems! (I was so happy :D). There was only one thing... The interiors of the Sylvan and Academy cities were displayed incorrectly. In the Academy, everything was brown, and in the Sylvan - completely black... But the essence remained... :D

So, I think you can find some similar patch on the internet... or, if not, I think there is still a point in creating it.