Hello, I see that Zinc (https://mods.factorio.com/mod/quirkycat_zinc) does not spawn when RSO is enabled. Could a config be created for this resource, ideally in the starting zone, or guaranteed somewhat close?

As a small bug report as well, the lack of Zinc was not called out in the console; "receive information about not supported ores (will be printed after game start)", this function may need to be looked at.

For my own curiosity, am I understanding correctly that modded ores must be specifically configured into RSO in order to spawn? Is there a GitHub that I can contribute a new config file myself?

There is no GitHub but you can post config link here or on forums and I'll add it. There is a description of config in vanilla configs.
Lack of it might not be called out because in spaced out config validation is currently not running with SA active I think. I'd need to check why - it was some complexity with validating configs of various planets.

@orzelek, sorry, what do you mean by "in vanilla configs"? Where is that?

All resource configs are in resourceconfigs folder in mods folder. mainconfig.lua is a big set of checks that load per mod config files when their mods are present. There are also base game configs that are always loaded: vanilla.lua and vanilla_enemies.lua.

I've adapted this just from a related bz config file.

function fillQuirkycatZincConfig(config)

    config.nauvis["zinc-ore"] = {
        type="resource-ore",

        allotment=100,
        spawns_per_region={min=1, max=1},
        richness=15000,
        size={min=20, max=30},
        min_amount=300,

        starting={richness=6000, size=25, probability=1},
    }
end

Same with quirky aluminum:

function fillQuirkycatAluminiumConfig(config)

    config.nauvis["aluminium-ore"] = {
        type="resource-ore",

        allotment=100,
        spawns_per_region={min=1, max=1},
        richness=15000,
        size={min=20, max=30},
        min_amount=300,

        starting={richness=6000, size=25, probability=1},
    }
end

Are those mods very similar to bz* ones?
If ore has same name it could be possible to simply enable same configs for them.

I said 'related', I meant 'similar'. I don't know what would be considered close-enough for that. I'm neither the mod author or very skilled with RSO.

I think it would be a big help if RSO exposed a method for mods to configure their own resources, that way you don't need to have a discussion for every new mod. Was something like that attempted in the past and rejected?

There was a plan for that at one point but it's quite complex. Mostly due to all the required validation on RSO side so that other mods won't start breaking things when passed config is not correct.

Added both configs to 7.1.4 - it is only for 2.1 if you are on experimental you will have it available.