well ok that doesn't seem too hard. Why don't you just import the buildings (or better yet reference them) without namespaces. Unless you need absolutley unique names them I wouldn't worry about it.

What I would do is when I add a building I would create a name for it (based on location on the map size etc etc) and then create a group with that name. Then parent the building under it once referenced in...

How does that sound? No namespace problems

Alan