Oh, for anyone else out in Blogspot-land who's been getting the "template not found" error- one last-ditch thing you can try (you will lose any 'customizations' beyond what's in your settings, but if you have them saved as a file somewhere it shouldn't be hard to reinstall them), is to click on "Template" and then choose a new template (ignoring the Blogger warning for "long term bloggers - just wait and we'll fix it"). That's what it took to get my blog publishing again.