Weee!
I figured out what was causing the loong processing;... I had checked all of the cloth collision options. After i unticked most of them, it went about business as usual.
As for the constrained group, I selected a small spot on the top of the hood, and the sleeve cuffs (I didn't select enough of one cuff, so I'll have to run another simulation...); and that made the item fit quite well.
The pose has the left hand in contact with the left breast; but this was remedied after the simulation, by slight repositioning of the hand.
I think in the next simulation, I'll increase the fold resistance a little bit, so the hood retains more of it's original shape. (... or maybe, I'll make the hood into a seperate dynamic group...)
Thanks Rayera, for a great tutorial.
Thanks Tormie, for your insight.