We have had large flamewars about all of the above topics. Discuss the characters, not the values of the posters themselves. If your posts aren't appearing at all. If you tried to post, but aren't sure what happened, do NOT post the same article to the newsgroup two or three more times. Usually, we will have seen your post the first time around.
Newsreaders are really funny things sometimes.
Some won't show you your articles until you exit the newsreader and restart it. Others might has a delay of a few minutes until your post appears. If you aren't sure how your newsreader works, ask someone at the help desk or send e-mail to your sysadmin. They will be happy to help you out. If your server doesn't get a group.