Hello Hansi,
this is a difficult job, and maybe even not possible. I once did it the same way by copying some project files and then I had the complete building. This method works, but it requires that one special file never must be changed: There is one file, that describes all wall forms and roof faces. If this file is changed by only one person, you cannot get a correct result. (You may not even push a wall or change a door or window size.)
The only thing to do is Dicam 1-1-6 and 1-1-7. You can take over all beams and panels, but they will lose their MOS structure. All imported elements will be in free construction.