I am posting this to share information in case anyone else encounters crashing problems. My aperture library is referenced. For the past 2 months aperture has been crashing regularly on me. Often after an import or while tryin to update a vault.. I finally solved the problem ( i think ). I updated my OS ( I wasn't even aware that I was running an older edition ) and then I created 2 smart albums: offline images and managed images. To my surprise there were images in both albums. I went through each image and reconnected it ( cannot stress enough the importance of multiple back ups ) and now it has been over 72 hours without a crash and I can successfully create vaults. Hope no one else has to deal with this.