Building in Zone 2 and am considering changing from my original plan of using spray foam. 
I would like to use Roxul ComfortBatt in a 2×6 stud bay and Roxul Comfortboards outside of sheathing instead. Plan on using a self adhering WRB and the baseplate will be sitting on a EPDM gasket. Would like to gather some more detail on water and air sealing with this approach, specifically:

1. important areas of the sheathing, framework and sheetrock to seal and the best sealant to use. This is a single story house sitting on a concrete slab with a single pitch roof.
2. transition between wall and roof WRB and air barrier at the overhang (2-6 feet long depending on location). I understand the WRB does not need to be continuous due to the overhang protection but how to deal with air barrier continuity best? What materials and where best to put them?

Thank you.