When initially setting up Live Writer with CS 2.1 it has some issues with the initial setup. Basically it doesn't work - at first.
After some sniffing, it's getting an Http 301 redirect that causes it to fail.
So, if you type in the site as http://www.cicoria.com/..... to the metablog api endpoint, it fails. However, just strip off the www and change to http://cicoria.com/.... and your good to go.