perpendicular wall opening for a window in a curved wall

[Anonymous]

howdy folks!

when i place a window in a curved wall, the wall opening that the window creates is somewhat of a conic shape.(3)

if i place a empty opening,the opening is perpendicular, thats what im trying to accomplish(1)

if i place the empty opening and then the window, it leaves two wall cutting lines.(2)

has someone figured out a way to have the perpendicular clean cut of the empty opening with a window?

thanks!
archicad 19
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