Eric: 
  
Thanks.  All very useful.  You answered the overall question, which is that once you change a default setting it doesn't automatically re-apply to items already drawn.  Thanks for clarifying. 
  
As to auto-build for the foundation, we're actually starting with the foundation first and inferring the first floor footprint from that.  Long story.  (Not the way I typically operate, but oh well!) 
  
Anyway thanks again!