Just because they're so nice, I decided to backup my Auto Awesome. Here's how to download them:
1. open this page: https://plus.google.com/photos/search/%23AutoAwesome (or go to Google+ Photos and search for #AutoAwesome)
2. click "show all" below the first photos from that page
3. select the first photo: mouse over the photo and click the tick icon.
4. use your browser's find-in-page feature (Ctrl+F or Command+F on a Mac) and search for from your circles. That's a different section which shows Auto Awesome photos from your circles and that's where your Auto Awesome gallery ends.
5. Shift+click the last photo above the "From your circles" section and you should see a message like "230 selected".
6. click "more" in the navigation bar and select "download".
7. You'll get a Photos.zip archive with both photos and videos. The filename includes the type of AutoAwesome effect. The archive should also include the "year in review" video titled 2013-MOVIE.m4v.