One thing you should never do with the SharePoint blog site is edit the posts/post.aspx page with SharePoint Designer. This page displays an individual post, any related comments for the post and form to add a new comment.
If you do edit the page, there seems to be no way of reverting back to the original functionality (trust me, I tried).
So I had to create a new blog site and tried using Access to migrate the posts from the old site but it only copied the Title and Published Date fields. The Body field for the new site is read only according to Access so I had to copy-and-paste the body content.
What I really need to do is apologize to everyone for the 300 new posts they are about to see, even though they are old. There will also be lots of people trying to access my old RSS feed which is no longer valid. I should have been using FeedBurner long ago but it's better late than never.
I have also reinstalled the Community Kit for SharePoint Enhanced Blogging Edition (CKS:EBE) since Vincent Rothwell (aka thekid.me.uk) provided a fix for the SPD problem.
I managed to find a sponsor to provide a new server for wssdemo.com :-) More on this later.