When I install it with MagicLauncher it gets to the Mojang screen then just closes.

Edit: I'm an idiot. I didn't read that it had to be in the mods folder. Sorry for bothering you.

Not enough detail to say anything. I do not advise using magic launcher for anything in 1.6, because it has a tendency to screw things up a large amount unless you know exactly what to do. It is much easier to use the Forge installer and the profile that creates in the standard launcher.