I've seen many people who's signature is a gif file. I wanted to upload one of those so I typed it in and it said, "Remote File Is Too Large." I tried uploading it from my computer but then it only uploaded one frame of the file. Why is it doing this?
I've not seen anyone with a .gif for a signature - avatars maybe, but not signatures. I'm pretty sure you can't use .gifs for signatures for that specific reason. I'm not sure though of course, I'm no techy.
I can tell you avatars work for sure. Is your .gif too large, either in file size or file dimensions?
Are you sure it was under the size restriction? It must be under a size of 64 kb or area of 500 x 100 pixels to work properly. Gif files do work in signatures for sure, though. I've had them in the past and Martin currently has one.