I remember witnessing two complete splendid performances of this magnificent polyphonic masterpiece within the same week, when I was a doctoral student at the University of Nebraska-Lincoln. Dr. Ritchie performed it on the famous landmark 17th century Dutch-style organ by Gene Bedient which stood at the time at Cornerstone chapel.
Dr. Ritchie has since released a complete DVD and 2-CD set of the Art of Fugue with FugueStateFilms. You can read more about it and watch the introductory video of this work here.
If you like Contrapunctus I, I have also prepared a practice score of this piece arranged for the organ with pedals with complete fingering and pedaling written in for easy practice and ideal articulation.
By the way, do you want to learn my special powerful techniques which help me to master any piece of organ music up to 10 times faster? If so, download my video Organ Practice Guide.