I see. I think I was confused.
Since I don't have the "newly created users" in any forum security groups, I had believed that those settings would not apply.
However, what you are saying makes total sense since as another user who has posted several times, works fine with compose. I guess the error message, as others have stated, isn't clear what's going on.
I'll leave it at 3. I already have 105 users in just over a day, but nobody is really posting yet...
Thanks very much for your prompt reply.
This forum rocks!