Hi Richard Leja,

Not exactly. When you start a new Punch design, you must define the ceiling height for each level (Design--> Default ceiling height)
If you define, for example the ceiling height for the first floor as 108"(the default in Punch is 96") Punch will adopt 108" for its calculations. So, if you draw a staircase, the height will be 108, because it is the distance between the floor of the first floor and the floor of the second floor. If you change de number of steps, or the extension, Punch will understand that you wish to do the changes, but maintaining the distance between both floors.
Of course, you can change that distance manually, if you wish
In other words, (and makes sense), the distance between both floors will determine the steps geometry but the steps geometry never determines the distance between both floors

Hope this helps

Patricia