You need to host the .gif on a storage site- it won't work just uploading it to DW. I keep mine on photobucket, and then use the upl;oad code from there.
NO - is possile to put up directly -
I make the animated gif with Photoshop, but of course there are other free programs for Mac and Windows.
When the gif is done you can check it easily when you drag the file from the dektop into a browser like Safari, Firefox, Explorer. When it works there -then it works also in our Forum - nothing Forum related with this.
Note: The maximum size of your custom image is 100 by 120 pixels or 293.0 KB (whichever is smaller).