well.....VIOLA! (sp?) I just found out from a good friend in the north east coast....you can.
Here's how.
you have to use a different opening object other than "Simple opening"
it appears theres an opening type which "does" indeed allow you to set wrap around drywall closure sizes....very slick.
...Bobby Hollywood live from...
i>u
Edgewater, FL!
SOFTWARE VERSION:
Archicad 22, Archicad 23
Windows7 -OS, MAC Maverick OS