I opened one world in an older version, and now none of my worlds will load on MagicLauncher. They work fine on the vanilla launcher, though. I even made backups before I loaded my Minecraft in an older version. I use Mac Maverick OS X.
EDIT: I ran MagicLauncher w/o mods and they worked. When I tried to use Optifine & Forge for 1.7.2, the worlds wouldn't load.
EDIT2: The world won't load only if I use Forge 1.7.2. Optifine 1.7.2 works fine.
EDIT: I ran MagicLauncher w/o mods and they worked. When I tried to use Optifine & Forge for 1.7.2, the worlds wouldn't load.
EDIT2: The world won't load only if I use Forge 1.7.2. Optifine 1.7.2 works fine.