Let me suggest what is bound to be controversial
Rather than "suppose"
that setting it from design mode might not work why wouldn't a person simply
test out the theory? And having done that there would then be no reason to
post "maybe that's the problem" because it uhhh, won't be.
Computer software development clearly isn't a "science" yet.
(To the original poster) Consider creating a new project, drop a picturebox
onto a form and add your animated gif image. If that doesn't work (confirm
the thing is an animated gif) and if it is, post the image or place it on a
webpage where one of us can download it from.
the