Some folks will cook bonein side up in the smokette,for the first 3 hrs,and when you open up,they will have pools of moisture in them.
This would be a good time to flip,maybe look over the ribs and take notes where you are.
Move the slabs around a little to even out the cooking.[End to end,sideways,etc.]
No real rules ,that I know of.
Nothing says ribs can't touch,or cook a few extra,if that suits you.
If you like to spritz,now could be a good time to spray them with some Apple juice/cider and a little Jack Daniels,if you are of a mind.
If they seem to cook slow in areas,move them closer over the firebox,or maybe the top rack.
Yes, you lose some time,but you are learning.
Yep,you will get some cook uneven by size.but that's learnin' and tastin'.
In my Smokette,I liked a minimum rack level temp of at least 225*.and a little higher, after flipping, never seemed to hurt.
Hope this helps a little.