Hi Steve,

You can create the arch in the main wall and the square window in a faux wall behind the arch
In this way you can set the properties separately

Notice that, in the situation above you can't texture the square window through the arch--> the windows' or doors' openings just render the surfaces as transparent, but the walls are still there

Patricia

Hi Steve

You can try these options
1 - 3D Objects library--> Exterior--> Windows and doors --> your will find several Archways POBs (Punch Objects)--> if you wish, your can modify these elements with the 3D workshop Power Tool
2 - If your arches are embedded in a wall--> draw the wall--> insert a curved empty door casement--> texture the trim with the same texture of the wall-->set the trim to the minimum thickness--> draw the second wall with the window behind
See this example

http://www.punchhelpers.com/residential1.html
(see the windows one the left, upper floor)

The recessed arch is in the wall (front) and the window in the wall behind

Patricia