clean it first with a soft angular synthetic bristled broom.
I would forgoe the priming. Don't know why you would need to do that.
I would definately use latex paint because (2) it will dry faster and not collect dust, second, the oil will remain wet for so long, I think it will cause more than usual droppings of the accoustical popcorn.
I would also only spray paint it, reason, using a thick knap roller cover will make more droppings and will require rolling the ceiling in all four directions, why, because when you roll one way the direction of roll popcorn will not get painted.
Spraying is so friendly to the popcorn, will cause hardly any to fall and will take a fraction of the time that rolling will.