I am running minecraft on my mac I wanted to install some single player mods the first mod I wanted to install was single player demands. That didn't work so installed too many items this worked fine, I then went back to try and install other mods and non worked all that kept happening was a black screen. Someone suggested Mod loader and it got to the white mogang screen then it came up with a little message that said minecaft has crashed, I have deleted the meta inf folder and everything. Just wondering if someone could point out what I am doing wrong.