I discovered an issue not letting me to install any mods. It reads "Forge Mod Loader has found a problem with your Minecraft instillation The mods and versions listed below could not be found Forge [7.7.1.661,)" When I uninstalled the mod it worked. My ForgeModLoader-client-0.log reads this
4/28/13 5:25:33.028 PM [0x0-0x5a05a].com.Mojang Specifications.Minecraft.Minecraft: Apr 28 17:25:33 Macs-MacBook-Pro.local JavaApplicationStub[35780] <Error>: CGContextGetCTM: invalid context 0x0
Please HELP! :'(