Quadrum is a mod that gives players ability to add blocks and items to Minecraft. It’s worth mentioning that these things have their custom properties. You can combine them with other tweak mods that exist to help you get some endless possibilities.
Full usage of this mod can get a little complex, so I encourage you to refer to the documentation section below. In short though, upon first running your game, a block and an item directory can be found in your config folder inside the Quadrum folder. Everything to do with Quadrum happens here.
Inside those block and item folders, you will store your JSON files that dictate what blocks/items should be created (info on that below) as well as any textures that are to be used, and localization files.
For Minecraft 1.10.2
For Minecraft 1.11.2/1.11