what does this option do? do ores get "spawned" when I landfill water, or do I get water and extract minerals from it? can I change this option mid-game?

???

If this setting is enabled, it will enable an option on the Resources tab of the game creation screen. If this option is enabled, Ground Water and Lithia Water nodes will spawn. These nodes can be harvested using Pumpjacks. Ground Water nodes produce regular Water. Lithia Water nodes produce Lithia Water.

https://imgur.com/a/1vJ8pmT

gets overwritten by angel's right? beecause on one of my runs with it enabled, I had no lithia water

Yeah, I believe so. Angel's should really be hiding that setting I guess 🤔