Flash Professional CS5.
fl.copyLibraryItem(fileURI, libraryItemPath)
fileURI A string, expressed as a file:/// URI, that contains the path to the FLA or XFL file.
libraryItemPath A string, that specifies the path to the library item to be copied.
A Boolean value: true if the copy succeeds; false otherwise.
Method; silently copies a library item from a document without exposing the item in the Flash Pro user interface. Call the document.clipPaste() method to paste the item into the new document.
The following example illustrates use of the fl.copyLibraryItem() method to copy the armjoint-l1 library item.:
fl.copyLibraryItem("file:///c:/users/userid/Desktop/Robot.fla", "armjoint-l1");
fl.getDocumentDOM().clipPaste(true);