Game Art Tab
In this page, you can specify the game icon and thumbnail that will be displayed in the Game Explorer. Either the icon or the thumbnail images will be displayed, depending on the View settings used in the Game Explorer page.
Your game is represented in Game Explorer by a thumbnail image, and in some cases, an icon file. You should provide box art or a similar type of logo for your thumbnail image.
Icon
The icon is used when Game Explorer is viewed in Details mode.
Thumbnail
The thumbnail is used when Game Explorer is viewed in Extra Large Icons and Large Icons modes. The recommended size for your box art graphic is 256 x 256 pixels. The image will be used for the main box art at that size, but will also automatically be scaled down to 48 x 48 to be used as a smaller icon, so you should test your graphic at the smaller size to ensure it scales well.