Wow James! Sorry I missed this post!
It is really easy to do what you are asking. Go into your album, go to the photo you want to change, and click on it. There will be a menu on the right side of the page title "User Options". Click the first option in this menu titled "Edit Photo". After the new page loads, if you look at the thumbnail image you will have options to rotate or flip the photo, as well as rebuild the thumbnail based on the new orientation.