Controlling which wall components connect together at wall intersections is of course critical. In most instances we can tweak the wall skin priorities to get what we want. It is a bit cumbersome however and of course different intersections call for different priorities. I would suggest that you should be able to select two intersecting walls, and then have the option to click which skins should connect together. The walls would always be drawn first based on the default skin priorities you set up but then be overiden for the individual walls when you click the tool (probably off a pet pallette). The result is the same as we have now, but far more user friendly and would be providing overrides.
Many Thanks, JP
John Peterson, AIA
Dalgliesh Gilpin Paxton Architects
Archicad 7-21 US
PC and iMac