Yesterday Blogger decided to muck about with the template for my book blog. I posted a blurb for Along The Penistone Line and then re-freashed the page so I could see the new post. Bizarrely while the main layout was fine the layout of each post had changed dramatically. On that blog I've always had the number of comments below the post and floated to the right, and the post title has had a background image, but for some reason these and a whole bunch of other things had changed.
I tried editing the template but each time I clicked save it reverted back to the previous version and lost my edits. I tried it from a number of different web browsers (Firefox, Chrome and Opera) so it was definately an issue with Blogger and not caching or cookies on my machine. In the end I renamed the post section from Blog1 to Blog2 which had the effect of deleting the post widget from the template and adding a new default one. This finally allowed me to edit the layout again.
I still don't know quite what the issue was, and even having spent a few hours I'm still not convinced that the layout is exactly as it was before. So the moral of this story, as with any story relating to computers, is to take backups. If you go to the Edit HTML tab of the layout editor Blogger will allow you to download a copy of your layout as an XML file. Everytime you change the layout save a new copy of this file so that if things go pear shaped you have a solid place to start from when repairing the damage.