Does this affect zombies on fire by proxy? Or the game has a difference for what kind of entity is on fire?

This is excellent. You have filled a huge gap for realistic game lovers. Thank you very much.

will be there update for other types of fires?

Can you do a mod that adds sheltered fires to the game to go with this?

i will recomend not only check indoors, also check the level of rain, lower kind of rain should not putout the fire, a storm fo course.

It has been considered but might not be added in this version.

Can even small rain extinquish it? It just checks if it's raining or not? Does it checks indors outdoors campfires so it won't automatically extinquish inside the building?

Как это работает!? Просто в реальности маленький дождик не способен затушить костёр, а буря вполне может! Это продумано в моде?!