You can use the Steps sill and head shape in the Ci Windows tool to achieve a lot of unusual shapes.
Just go to the Shape portion of the tools settings, set the head or sill (or both!) to Steps, and then hit the little button to the right of it:
The Array Values dialog that will come up let you set the offset from the base (or top, for a Head shape) for each step. So entering 0 will mean that segment is not stepped, but 1100 will make it stop at 1100 above (when using a Sill) the bottom of the window
Then, just hit OK when you're done.
Note: the segmentation of the steps themselves is controlled by the amount and size of horizontally placed panels you have in your Glazing setout