Here is the completed Magic Square, after spending a bit of time on the blocking board.
I used about 1 ball of DMC Cordonnet Special in size 50, and the project took somewhere around 60 hours to tat. The finished square measures 9.5 inches across and 13 inches diagonally. You can get a better idea of its size in comparison with this blocking board:
I went to a few craft stores looking for a frame, but couldn't find anything I really liked. I was hoping for a round frame and didn't realize that the craft stores around here don't sell them. In the end, I settled for an inexpensive square frame, just so that the tatting can be displayed and protected. If I see a nicer frame later on, I can always switch out the tatting.
I've been spending some time trying to write up instructions for this pattern and it's proving to be very challenging! Due to the nature of the design (see here for the possibilities), it requires many diagrams and a sort of "choose your own path" for the written instructions. I'm going to persevere and hope to get it done and posted to my shop in a few weeks.