Also i would like to add that it stops on 33% (atleast it did for me and my brother).
* NB: i do not take credit for these steps i got all my information from This post was a little outdated and i just wanted to make a post updating /r/Leagueoflegends on what you have to do to get LoL running smoothly.
After multiple attempts i found this subreddit and the post in the sidebar ( ) A few days ago i tried to get LoL to work on my mac.