Minecraft Mods Not Cooperating On My Mac?

Mac's are coded completly differently to PC's. Most mods have only been designed to comply with PC, It takes a lot of extra effort to make them mac compatible so most developers don't. Most don't know how as they only work with PC! It's not your fault i'm afraid it's just the pure fact PC's are much more popular to have things coded for than mac's and the mac version is typically always done much after a PC make. You will have to wait until the mod developers officially release a mac version!