A couple of items to note:
I set up the meta provider and was working fine with the expandable text/html.
I upgraded to the MetaPost release 1.2.6 and now get a Server Error 0 Occurred when trying to retrieve the post.
I can set up a new expandable text module on the DNN server and access it with MetaPost, but later when I try to update the post i get a Server Error 0 Occurred.
Secondly - I if log on the site and make a manual edit to the post I will get the Server Error 0 Occurred, unable to retrieve the post.