Very nicely done.
It\'s possible the Dullcoat was a bit too shiny because you didn\'t shake it enough.
The part that \'dulls\' is heavier and sinks to the bottom. I\'d say sit the spray can in a tub of very warm water, and then after a bit, shake the living bejeebus out of it and try it again. A light dusting, once properly mixed will be all you need.
Of course, if its not that, I\'d say try another brand!