Fulgoran Enemies (https://mods.factorio.com/mod/Electric_flying_enemies) dont spawn while RSO is enabled, even if I disable "Use RSO biter generation", if RSO's biter generation is disabled shouldnt that mean it would generate enemies as if RSO wasnt enabled or does that do something else (or a bug?).

You also have to enable startup setting to use vanilla biter generation.
I'm not sure if this will help with modded enemies - it depends on how they are generated. RSO ignores resources on Fulgora but maybe I need to make it ignore something else for enemies from that mod to spawn.

You are indeed correct I had actually missed that startup setting! It does indeed work now I can see them generating bases with Use RSO biter generation enabled and disabled as well, with both use vanilla biter generation and use RSO biter generation does that mean extra enemies will possibly be generated on Nauvis for example if I leave both enabled?

Thank you very much for the help!

Hopefully if someone runs into the same issue they can see this thread too.

Yeah with both enabled Nauvis bases will be generated by both base and RSO generator.
I might take a look at some point to check why RSO disabled fulgoran enemies (and make it ignore Fulgora better maybe).