When you disable animations you will see an image instead of a moving horse. The still images of the new horses have backgrounds as well, so in the stable you will see the stable background. This does NOT mean that you did not disable animations.
Yes, the old images had white backgrounds and no, the new images will NOT go back to white backgrounds.
While the old still images looked 'better' than the new still images, the old generating technique will no longer be used.
The new technique will allow new manes, new wings, new breeds, while the old one was designed for still images only and not animations.
While we still plan to offer the possibility of disabling animations, keep in mind that maintaining the non-animated version is not a priority.