Information

Minecraft version: 1.21
Modloader: NeoForge
Version: 21.0.98-beta
Environment: Singleplayer

Mod name: Alternative World Save Location
Mod version: 1.21.0-3.5

Question

Can this mod be used to load saves from a different drive (other than C:) ?

Also can it be used to define a custom path for newly created worlds?

Yes that should both work, thanks for giving the mod a try!