The rating requirement is 2000-2199 but what performance norms do I need?
i don't really know, but CM isn't uscf rated, it is fide rated and requires 2200+ rating, or you can go to special tourneys and lower it, for instance, the Pan American one.
CM is harder than NM in my opinion
if you go to this pdf
http://www.glicko.net/ratings/titles.pdf you will see that uscf has cm title at 2000 with norms