You'll add a folder to your Archicad library using the Library Manager.
Put your new things in this folder to keep them distinct from the original Archicad library that gets updated all the time.
Once a picture is in this folder and the folder is loaded into the library, you can put its name in the object's image call and it will appear within the picture object.
This is how all new things get added. Beginners must remember that unless a thing is formally added to the library it will not be accessible. If Archicad is running when you add elements, the library must be reloaded in the Library Manager.
"Pirate" is so declasse. "Conquistador," please!
Dwight Atkinson