I think I found the problem.
http://www.llamaserver.net/admin.cgi?game=Madness
Look at Madness, it's running "Single Age Mod" but Procyon is running "Single Age Complete".
http://www.llamaserver.net/gameinfo.cgi?game=Procyon
I think you need to remove the single age complete and put in single age mod.
Also, I got the same error you did when trying to submit.
Jazzepi