Open the Library. Open the Groove Agent tab. Click on the gear icon, upper right hand corner. A line of text will appear “Library default location” and an empty space. Click on the FOLDER on the far right hand side of this empty space…and then direct the Library to the folder holding your VST Sounds for Groove Agent. Then DOUBLE CLICK on a file that you know to be a Groove Agent VST Sound file.
The Library should then establish a link to all your VST Sound files for all your various VST instruments.