How to bring back libary parts into a TW file from a folder?

[rob2218]

here's the scenario....
I created these stairs with specific names.
about 30 of them.
they were in the 'embedded folder' of the TW file.

now they got removed and deleted and the stairs are no longer editable....i need to put them 'back in' the embedded folder in the TW file?.....how do I do that in one shot?

[Laszlo Nagy]

This page:

http://helpcenter.graphisoft.com/guides/archicad-17-int-reference-guide/interaction/editing-elements...

says the following:

Dragging and Dropping GDL Object Files
You can drag and drop GDL Object files from the MacOS Finder or the file manager directly into ArchiCAD Projects, the Object Settings dialog box or the Embedded Objects folder of the Library Manager.
Dropping an Object into the Floor Plan activates the corresponding tool in the Toolbox and the newly placed element becomes the default element for the given Object type.
• It is possible to place several GDL Objects at the same time using Drag & Drop.
• Windows and Doors can only be dropped into a Wall.