I had the same problem with trying to paint a stucco ceiling and ended up purchasing an electric power spray painter (not very expensive), I draped everything that was not ceiling in plastic and got to it.. I did not lose any of my stucco ceiling, it turned white before my eyes and bonded the stucco bits so that next time I have to paint, i can use a roller,, one bonus i had was that i did the entire house in about 3 hours, all the ceilings.. but the dust from the paint was everywhere, so make sure you cover absolutely everything.. I used a latex paint, but home depot told me to use an oil due to the fact that the water in the latex will swell the stucco and drop, this was not the case. you don't need a lot of paint and a proper mix of latex paint and water was needed to exit the nozzle..
hope this helps.
experience is the best teacher.....