That thread explains why 4g!fs is/most likely always will be banned (Post #10 in particular).
If you don't have gif editing software, I have a suggestion for you. If you find a gif that you want to post, but it has that watermark, drag the gif to google image search. It will pull up several sites where that gif has been posted. Try to find one that doesn't have the watermark + is hosted on a Sherdog-friendly site. That's what I used to do before I got my gif software.