On one hand, sorry for being a pain, being potentially the only person poking these without SA enabled 'cause your ores mod is spectacular, on the other, found more! :)
Failed to load mods: __quirkycat_base__/prototypes/seeds.lua:27: bad argument #1 of 2 to 'pairs' (table expected, got nil)
stack traceback:
[C]: in function 'pairs'
__quirkycat_base__/prototypes/seeds.lua:27: in main chunk
[C]: in function 'require'
__quirkycat_base__/data.lua:8: in main chunk
Looks like pairs(data.raw.plant) needs an or {} in a couple spots there (27, 38, 49), or otherwise gated around those existing (or sa being on)
And adjusting that landed on
Failed to load mods: __quirkycat_base__/data-updates.lua:49: attempt to index field 'yumako-seed' (a nil value)
stack traceback:
__quirkycat_base__/data-updates.lua:49: in main chunk
Which just needed gated around if mods["space-age"] (to match the block right below, or more narrow gating on those existing)
And... that reached an error of
Failed to load mods: Error in assignID: item with name 'tree-seed' does not exist.
Source: tree-01 (tree).
Which I just gated the whole tree-seed block at the top of seeds.lua with if data.raw.item["tree-seed"] for, which seems to have done the trick.
Not sure if in the grander scheme of things with your mods, you'll want to go that route or the whole "if space-age" boundary on the seed stuff, or just make space age non-optional for useful wood side things.
