Compare Selected Snapshots: Preview Tab

Select the desired Snapshot thumbnails in the Snapshot section by holding down the Shift key and clicking on each Snapshot. 

Optionally, click the Select All button.

Click the Compare Selected button which will open the selected Snapshots into the Snapshot Preview screen. 

On the Snapshot Preview screen, select how you would like the Snapshots displayed from the dropdown control.

The Snapshots will be displayed as requested.