Yes, dry time is important IMHO. I let sit an hour tween coats in warm but not humid weather. Also did mine in the shade.
Dunno what happened with your Preval sprayer, DO NOT SHAKE it, the cap has a vent hole, it you shake it, it will leak, i found that out the hard way too. Also dont overfill, and always keep the sprayer upright for the same reason. I ended up with dye on my shirt and shoes, and I was trying to be really carefull.
Since the dye is diluted for the spray, the pigment goes on lighter but wetter and requires more dry time. I suck at spray painting so I had a few runs which eventually blended in OK, but resist the temptation to spray more to fix somthing without letting it dry first, thats a sure fire recipe for runs. So spray lightly and let dry fully before going back to fix things. Yes "LEAVE IT ALONE JON!" is exactly what you should do, hehe, at least until it dries fully. Adding more while its still wet is just going to make things worse.
Maybe your sprayer was defective, I dunno. Used carefully I thought it was fairly impressive, tho I did get a bit messy too.