1. The greeble pack comes in a ZIP archive, use the software of your choice to extract the files inside

2. Once extracted you'll see the greebles are arranged in folders, please move the folders to a more permanent location somewhere on your drive

3. Open up Blender and go to Edit -> Preferences -> Add-ons

4. Here you'll search to find the "Generate Plates with Greebles" add-on that you already have installed and open up its settings

5. In the add-on's preferences you'll see a big button called "Add Folder Containing Greebles", hit it a number of times and then add, one at a time, all the folders you extracted from inside the greeble pack

6. Once you've added all the folders please press the "Refresh Libraries" button at the bottom and then go to the very bottom left corner of the window and click on "Save Preferences" for Blender

That's it, all done, enjoy the models guys and please do let me know if you spot issues with any of them and also let me know what other models you'd like for future updates to this pack.

Thank you very much and I'll be seeing you around, have a great day.