I would advise against making your first build with a carbon rim and an expensive rear hub, and here's why; First off your spoke count is more than likely under 32h, which means there's less margin for error when it comes to trueness and equalized tension. Since your carbon rim is a cheap Chinese or Taiwanese product, the 50mm rim depth is a dead givaway, manufactures suggested max kgf is vitally important, otherwise your at risk of pulling a nipple right through the rim and ruining it if you run the tension too high. You just cannot run as high tension levels with carbon as you can with alloy rims. Have a reputable shop with a decent wheel builder do this rear wheel for you. If you really want to learn how to build wheels, start out with cheap alloy rimmed trainers and higher spoke counts.