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Welding of studs through deck to steel beams

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We have a project using exposed steel beams under acoustic composite metal deck.  This is normal composite metal deck, with a flat perforated sheet of steel spot welded to the bottom of the deck.  Batts of insulation are then stuffed into the resulting cells.  I believe the perforated plate is painted before assemble.
When shear studs are then welded through the deck to the beams, they have to pass through two plies of steel.  Two questions arise:
AWS D1.1, section 7.4.2, forbids paint on the top flange of the beam.  I am concerned about the possibility of rainwater wicking between the deck and beam, rust blush forming on the beam flange, and then weeping down onto the beam, either requiring re-cleaning before painting or staining the paint after it is applied.  If two layers of metal deck, at least one of which is painted, don't compromise the stud weld, does a coat of shop prime on the beam flange?
Second question:  D1.1 section 7.2.7 forbids welding through more than two plies of deck.  Obviously, they will try to butt the deck sections where they can, but I am guessing there will be places where they will want to overlap sections of panel along their edges.  With our acoustic deck, I assume this means that at overlaps they have to cut or punch a hole in the top section of deck.  Since this will be a fight with the contractor, I would appreciate confirmation or thoughts on this.
Mike Hemstad
Minneapolis, Minnesota