Hi @ErikaGanda!
That's a new one. I think you may have gotten bitten by the OS X limitation of 3-days walltime before it starts deleting files. How long was the process running for? If that's the case, then you could try the steps in this post to deal with that for now.
Does the moving pictures tutorial work? Does re-running work?
That is expected, so I think everything is ok there.
Thanks for your patience and help!