Hi, I am currently building some dynamic components, "pcmoor", for building construction. I too have been frustrated, however I believe the problem is in editing independent of the main model. For example before reusing a previous component to build the next, copy within a main model, then make all parts unique, use the outliner to select all the sub components at once, then make unique. thus any changes will not effect similar components. Then if you want too place into another file. One day someone needs to write a book....interested?
cheers
Philip