Thanks as always for posting this. I don't know where you get the time, as I barely have time to check this forum every few weeks! The only reason I'm here now is my CNCs power supply died and I'm waiting for the new one.
Anyway, I tried this gadget on Vcarve 10. Maybe I'm not configuring things correctly but I'm not getting the results I would expect. I used all of the default values and chose the 3 different options on "Select Step Configuration". It seems that the stringer is a set angle and doesn't adjust pitch when you choose a less than ideal step configuration. Also, I get a dogbone on my nosings.
I attached a .jpg image showing what I get with the 3 options.
I have been rewriting the Stair gadget in the Gadget Boot Camp video series. Look at this version and let me know if it works as you need it to.