Transferring shapes/models.

This is probably an FAQ but I could not see an answer readily.

I have a drawing that I generated through reverse engineering a project. Now
that I have created alot of drawings I am finding that there are additional
shapes and objects that I need. If I reverse engineer the whole solution then
I get the objects and shapes but that file does not have the drawings that I
have created. I need to either transfer the drawings to the "solution reverse
engineered" file or transferr the objects and shapes to the file that I have
the drawings under. I am not sure how to do either.

Thank you.

Kevin