When using any powder, the archive will be damaged and the corresponding world can only be deleted. My English is not very good. Please give feedback to the author.
I tried editing the save, deleting blocks, chunks, and mca, but the archive couldn't be repaired.
https://paste.ubuntu.com/p/7cTJ3gtHNj/

fix now

I've reproduced this, what does "fix now" mean?

In our case, removing the mod, loading the save, and then re-adding the mod at least saved the world, but clearly this mod feature is broken. What did you do to resolve this, @KuroPeach ?

Ah, I see, fixed in Nature's Aura 39.2, and thereby with a more recent version of this modpack: Ellpeck/NaturesAura@791c6ad