1. Sprites support GIF format, too.

2. GIF PROPERTIES are:
Loop - repeats the gif until the overlay ends. If you turn off the Loop, gif will repeat its action as many times as it is in the code and then stops;
Reverse - the gif animation goes backwards;
Speed - from minimum 0.1 to maximum 5 you can set the speed of the gif repetition. The default speed is 1 that is equal the speed define within the GIF.
