Ok, I've decided to add some mods that already have a config file provided in the config folder, I'm mainly interested in Mekanism, Ender IO, Carpenters Block, Chisel Mod, Xeno's Reliquary and Extra Cells, now I know for sure I won't have the Osmium ore from Mekanism generated in my world and my plan for that is to use a Mystcraft age (I delete one of my age regularly for mining purpose and to avoid having a large save file) to get this resource, but I was looking at the config file for Mekanism and the Osmium generation is set to false in the config folder of the FTB pack, do I need to enable it or Thermal Expansion COFH world does take care of it somehow, I'm not familiar with this mod at all... I think the rest of the mods I want to add don't really have any kind of worldgen that I should take care off, but maybe I forgot something here, any help is appreciated...