Probably you wish (like me) something like this:
With the generated objects:
Only with polylines (staircases invisible)
The last staircase has the polylines manually arranged.
For this I've use a Open Source principle:
"Don't like what it is, grab the source and DIY".
For my personal use I've modify a little the Staircase generator given to us by Emmanuel.
It look something like this:
For simple stairs it work somehow but, for combined stairs, I wasn't able (read "I'm too dump") to make it work as I wish.
Anyway, while I don't draw staircases everyday I accept to make some extra work.