I have figured out how to create a roof but I am not able to find the edit roof window that allows me to add skylights, dormer, windows,etc.
I have been using this tutorial-
http://www.novedge.com/Generic_View.asp?LID=2489&SKU=1473&AFTK=NV1106
Got to the first "edit roof" window but not the second that allows windows to be added