Basically avoid changing the xml files under content for dasBlog, you will mess up your blog. I did this in an attempt to make a post that I started on the 7th but posted on the 8th go back to being on the 7th… First I just changed the CreatedDate in the content xml and this almost worked, the post would intermittently disappear from the site (and the file). Luckily I had made a backup of the content files before I did this so I could just put the post back up when it disappeared. I quickly realised that this was a suboptimal solution! So I moved the post over to a new file with the correct date in the name. This file was eaten up by dasBlog and mysteriously disappeared, although I didn’t notice it for about a week. What had happened was that I had got the date for the outer element set to another day in conflict with another file. So dasBlog just kicked it. Once I had got the date right it still took several updates for the change to propagate. Now I hope I have saved all my posts!
