Upon further searching I found the signature compliance guidelines and now understand why my signatures have not been working. I will see what I can do to make the signatures forum friendly. Although, I have not seen any signatures on the forums at all despite having signatures enabled. I only see avatars.
Edit: I have confirmed this. Based off of
these guidelines. I changed one of my banners to meet specifications, which you can get
here. The banner did not show up for me and I have yet to see any graphic signatures on the forum--I only see text.
Did I find old guidelines. Do other people see images in signatures?