Sims 3- Freezing whilst installing onto my computer

Hello,
Im trying to download sims 3 onto my new computer (macbook pro), ive logged into origin and i've downloaded the game, both with no trouble. I now want to install it so i can actually play the game but when i go to install it, it starts 'copying files' fine until it gets to '841 out of 899.' Its now been like this for a few days and i've restarted my computer already. What should i do?

Many Thanks :)