>Then later, I start a new project in a new folder structure, f:\myproj2. And, to start out, I copy all source files from the old folders to the new, the original include reference breaks because it's hard-coded to the old 'include' folder in the f:\myproj hierarchy.

Do you use a framework (commercial or one you've written yourself)? It soundsd like you don't. That would most likely clear up some issues for you.