To add new curtain wall frames:
Click the Edit Curtain Wall tool from the Building Shell tool set, and click Add Frame mode from the Tool bar.
Select the curtain wall to edit.
Click at the start point of the new frame, and then click the end point of the new frame. The start and end points must be placed on existing frames.
Press the Shift key to constrain the placement of the second point of the frame horizontally or vertically.
The frame is added, acquiring its attributes from the curtain wall grid settings.
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