DF Ores and adding to all biomes

[Mskitten87]

so i have spent the last 2 days going through trying to get all the DF Ores to spawn in all biomes i have the boulder rocks working but how do i go about getting it so they also spawn under the map/generate? trying to add it so each biome has all above/under but am having a hard time doing the under the world one.