When you click the Create Stair button in the Stair Tool's Info Box, the Dialgo appears where you have to select which type of Stair you wish to create. Select the type "Single Winder at Upper End", which is the leftmost Stair in the 6th row.
When you get to the StairMaker Dialog, set the number of Winders to 1 from the default 3. Also set the Top Tread below Floor Level button in the bottom middle of the Dialog.
Then you should first set the main height, length, width values for your Stair (in the upper left part of the Dialog), then the others: numer of steps in each flight, upper and lower offsets etc.
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