Following the link to "a sample real-live gallery in action" (http://www.moonriverphotography.com/gallery/2144279#111442318) was a dead end. It requires a password. Not the best example, I'd say.
I'm a new to the pro version, but I would like to offer one suggestion. When you replace a photo that a customer has ordered, you now lose the original. For instance, a customer ordered an 8x10 that didn't crop well, so I adjusted it with a replacement. Unfortunately for me, I had to add back the original which was better for a 4x6 crop. Thankfully, I still had that image.
I'd love to see a feature that keeps the original image as well as the revised image, and have the images saved with the replacement to the right of the original.
I love this site. Keep up the good work!