Can I put all my objects into the Embedded Library, as a way to archive my project?
This NOT recommended. This would result in a very large-sized file and associated speed problems (e.g. with Autosave). Moreover, since you cannot drag a folder (or an LCF or PLA) into the Embedded Library, it is not practical to embed all of the libraries used by your project as a way to archive. Many objects (like doors and windows) use macros, which need to be loaded as well for the object to work properly. The preferred format for archiving is to save as PLA.