Mac 10.11 ( El Capitan ) Crashes

I don't know if it happens to someone else, i've seen a lot of people complaining about that LoLPatcher doesn't open, but that's not my problem. My problem is : Sometimes ( like 4/5 times ), when the Accept/Decline thing pops-up, my game crashes and the Crash report open. It also happened once, that, i did get to pick a champion but then i crashed, not when picking my champion, i crashed when everyone picked theirs but i don't know if it is connected or not.. Also, it happens that sometimes (2/5 times approximately) that it crashes when i press the "play" button. I'll put the crash report in the comment if it can help and i can also try to record some crashes. Thank you!