You can deepen your knowledge of ARCHICAD's Stair Tool with my video course, available on GRAPHISOFT Learn: https://it.learn.graphisoft.com/visit...
In this short ARCHICAD video tutorial, I'll explain how to draw a custom-shaped Stair in ARCHICAD.
This video tutorial was recorded with ARCHICAD 23, but the function described is available in ARCHICAD 21.