Rekordbox Keeps Crashing

Hi there. I subscribed to Rekordbox back in October and after about a week Rekordbox started crashing saying an "Unexpected Application Error has occurred". I got a new laptop yesterday, it's an 2008 MacBook and my buddy download rekordbox on it for me and used his controller and it had no problems. But now it's crashing on me? I'm a DJ and I have shows this month and I am risk this crashing on me during a show. I need any help y'all can give me! Please hurry!!