Within Enhanced Tiles after selecting the number of tiles that you wish to have in your subject site, you need to hold down your mouse cursor and select your desired hover effect option.
As noted before, you cannot leave your customization options as default.

Also, before pressing the submit button in Content Layout Tool environment by hovering in between your chosen Tools, you will notice that a plus sign appears, hold down your mouse cursor and add more tiles while holding down and dragging your mouse cursor to the number of the tiles that you wish to have in one row.