I think everybody can understand the frustration of having to start something over. Today I've been wrestling with implementing staircases, and I've ultimately come to the conclusion that my approach is not a good one.
On the one hand, I feel like a putz for not making any progress and wasting time, but as they say "I haven't failed, I just succeeded in finding a way that doesn't work", heh. I'm going to take a step back from the staircases (No pun intended) and attack them from a different angle conceptually.
For those of you desiring a more technical explanation -
My initial plan was that building a staircase indoors would cause all roof pieces for that particular room to disappear and be replaced instead with floor pieces. Thus, adding a staircase would essentially convert a section of roofing into a second floor. Where this falls apart is when considering things like.. for example a catwalk that isn't indoors at all. Without a roof to convert to a floor, the staircase is suddenly ineffectual.
It was also my intention that stairs and floors be built realistically - no giant platforms hovering in the sky without proper supports for example. Seeing as this seems to be the order of the day in most other construction-based games, I am re-evaluating the merit of this approach.
Anyway, I just wanted to keep you all updated. I'll let you know how it goes.