I use the PMDG logo in my signature but it is rather like preaching to the converted to only have it showing in the AVSIM forums. Is it permissible to use it elsewhere which will presumably mean linking it to Avsim or is it available to upload to other forums.

Bill,the forum signature you are using is uploaded on the PMDG server, so therefore you can use it in any forum you wish.Sincerely,