I'll try to reply to you.
1.It is designed to work with a mesh screen in the bottom, even with flowers and it adds some convection. Replacement screens fit the silicone part in the lid (to avoid to get flowers in the stainless steel tube.), not in the bowl.
2.Depends your preferences, test all. Personnaly I like to start at 1 or 2 (it depends the moisture level) for one cycle and switch to 3&4 for another one cycle.
3....? to put your lips on a smoother surface than straight stainless steel tube, but maybe I missing something here....
4.Slow to medium draw is better, hard&steady draws carry too much air but is possible when you are vaping on a full battery. No wait, when you get solid green light, you draw, although it is better to wait 10-15s between hits to get optimal performances (but it depends the battery level too, with full battery there is quasi no wait and with a 50% charge you need to wait for better vapor).
5. This vape is really idiot proof, it was working well with grind and no grind, moisture or not and even with different drawing style. I f you are a cloud chaser be sure your flowers are dry enough, grind it fine pack the bowl and start at 2 or maybe 3 if you get an iron throat! If you are a taste lover scissors cut your load, don't pack it too much and start at 1 or 2. I like to put a bit of ungrounded flower on the top of my load to avoid top lid screen clogging (I was using another screen on the top of the load too but it was annoying so I prefered the tiny piece of bud).
I hope this help, I love my Prima and can't understand why it is so underated here....maybe cause it's not really designed to work with water tools....
