After going all the way around the edges, we end up with this beautiful image. Extractions are the most time consuming part of the design process for these mandalas; so anything that can speed up the process will help. You will figure out your own ways to save time as you get practice. I understand that you CS3 users have other, powerful tools at your command. The process here in Photoshop, is very similar in Corel Photo/Paint. I have not worked with other programs, but there are other options out there.
To my mind, they are all magic. I look at this beautiful image and my heart swells with gratitude to have these tools. To be able to work with the amazing beauty of nature in this way is humbling.