Hi,
Yep, that's the typical message for not adding one (and only one) of those two tags to the template.
The template does have built-in instructions on how to add elements. They used comments, e.g. <!-- This is a comment! -->
For the description section tag, you'd add [DESCRIPTION]. The one-page lister would then locate and use that tag to add your description text to the listing. You add the appropriate tags, just as I've done the description tag for example at practiceboard: http://www.practiceboard.com/?9924933
Danno