Currently all this mod does, is disable all vanilla ore generation.
(Mod ores will generate normally unless disabled in their own configs.)
Based on my quick testing, it should also work at least in Mystcraft ages.
Re-hosting the mod file publicly in 3rd party sites is not allowed.
Mod packs: go ahead, as long as you are not making money with the pack or violating other permissions.
Basically follow Wheaton's Law (= Don't be a di*k.).
Some mod packs may want to do something special which requires no regular ores in the world. Or some people might want to play like a challenge type play-through, where you need to get everything through villager trading, or other mods.