https://sourceforge.net/apps/trac/sourceforge/ticket/14550
I'm unable to add icons to my project or to subtools of it. I would have supposed that any gif or png would be ok, but If I try to upload within the Admin tool, i either succeed in creating a completely white square, a completely black square, or more than often I receive Error 500, We're sorry but we weren't able to process this request.
Confirmed, I tried uploading an icon the user supplied to my test project, and it just resulted in a black square: https://sourceforge.net/p/fancypants/home/
custom_field__size: 2 --> 2
assigned_to: Wolf