Important notes:

RSO doesn't work with map preview - there will be no ores there with RSO active

Railword preset increases size of resources significantly - if you use it with RSO fields will be much bigger. Stay with Default preset when using RSO.
Starting area size multiplier is taken directly from map settings - using large values (like max of 6x) will result in a very big starting area with large distance to first non starting resources. If you want to play like this you can use starting area richness multiplier in settings to make starting resources more dense.

Mod changes resource spawning to be region based - by default regions are big which promotes using of trains. Resources will be more sparse so more logistics will be required to supply your base. As a bonus resources further away from start location will be more rich.
Important - frequency of resources works differently with RSO active. Frequency set in map settings menu will make resource more or less frequent in comparison to other resources. Enemy base frequency works normally (there will be more or less bases based on setting).

RSO also controls spawning of biter bases to make it easier for a player to move further into the wilds, but don't expect resources to be biter-free.
Mods that don't modify resources should work without problems. Support is present for most of large mods (Bob's mods, Yuoki industries, Uranium power) and some of smaller ones.

If you receive information about not supported ores (will be printed after game start) please post in discussions tab and I'll try to add support for them (please write which mod adds the ores if possible).