Hexxit crashing on Man

[yello4]

I run on a mac and whenever I try to launch Hexxit it crashes. I played on it before it was built into the technic launcher and it worked like twice before I deleted and used the one put in the launcher, but it crashes every time. Note I am relatively new to Minecraft (Since March) and don't know much about the inner workings of stuff.

[Maxis010]

You played it before it was built in to the launcher, impressive, since it was made by the Technic team and only available in the launcher