Some objects, like windows and doors, are version specific and that is why the migration libraries exist in the new releases.
In AC13 any new object you create can be embedded into the file.
The correct procedure at the end of a project (I do it also at the end of a major phase) is to save the project as an Archive (.PLA) this will embed only the objects used in that particular project.
Eduardo Rolón AIA NCARB
AC29 US/INT -> AC08Mac Studio M4 Max 64GB ram, OS X 10.XX latest