When you want to make a post, the form goes from:
Username: (your own)
Subject (optional):
Icon (optional)
BB Code
Message
etc.
Have you tried filling in the subject line with something, like I\'ve done? (\"subject goes heeeeeere\")
Is the \"One or more fields are not filled out correctly\" message exactly the same when you try to send a PM? Can you try sending one to me, just typing \"test\"?