Dave,
Really appreciate your quick reply. Here's the info under my Settings' Blog tab:
Under the Blog tab, I have checked the box that says "Check this box if you want to connect your outline to a Wordpress site"
the name and password are the admin password for my blog.
I tried UNCHECKING the box to pass the text through Markdown, but that didn't make any difference.
I still get the error I mentioned above, but the post is created, but also a new post is created when I edit or add text to the post and press the Wordpress button again.