You can add an image background to a Live 3D model for the web by adding a few lines to the meson code:

Applet.Primary.fill="FFFFFF"; /* Background color goes here */

Applet.Primary.image="stratalive_400.gif"; keepDisplayImage=true;

For more information, see the Meson User Manual. From the Live 3D CX main menu select Help > Meson Language Manual.