The Unassigned Openings section displays a list of the openings which are not currently assigned or associated with an art image. 

The listing displays the template number, and the X and Y coordinates of the opening's position on the mat. 

These are usually openings created within Designer then brought into Visualization.

Create a project in Designer.  

Click on the Visualization icon in the upper right of the screen.

The current design is brought into Visualize.

The openings within the project will be listed in the Unassigned Openings section until they are assigned to an art image.

To assign the unassigned openings to the art, see Add Art Region from Opening.