OK. Let's take the following scenario: you want to create a new object and save it on a local server in your office.
There are multiple ways to do this but let's follow a simple path. Let's make sure that you have a "clean slate" file open with only the ArchiCAD 18 library attached and no embedded objects and then:
1) You select your Morph and Save Selection As Object.
2) When prompted for location to save, you choose
File in a selected folder and pick a
Folder
on your server, the same one where you keep your custom library parts available to your coworkers. Make sure that you check the Create New Object at the bottom of the Save dialog box.
3) You go to Library Manager, add the
Folder
as your custom library and finally Reload all the libraries so your project will load your custom object(s) for the first time.
4) In ArchiCAD, find your new object in the dialog box and
place it in your file (ArchiCAD will usually automatically select the object you've just created).
[EDIT] 4A:
Select the custom object you just placed in your plan view.
5) Open it for GDL editing by clicking
File > Libraries and Objects > Open Object.
6) Make your changes and press Ctrl+S to
save.
Now, when your coworkers have the Folder linked as a library, after they reload it, they will also see the changes you've just made.
You may learn other procedures, for example, opening the object straight from the server, if it's not loaded in your current project, but the above procedure will ensure you only have ONE copy loaded (there is no embedded copy). With a BIM server you have to include an extra step to reconcile the
file server
libraries with the
BIM server
libraries and then reload into your project, but that's a different approach.
I hope this helps.