After the window cavity is filled with insulation, how should it be handled in terms of vapour barrier? The rest of the walls get the 6mil poly. Should the poly go right over the window or should it be cut and wrapped just like it would if the window was being left open?
No, putting two waterproof layers together is a formula for moisture to collect in between and mold to form. If you feel the need you could add a window film tinting or frosting the window, assuming you smooth out all the air bubbles.
Digging up this thread as I now have 4 windows to plug in my new space. Can I run electrical in the "void" between the window and drywall? I'd like to reclaim that wall space for some lighted poster boxes, but would need to run electrical.