Support frequently gets refund requests from WordPress theme buyers who believe that the theme which they have purchased is broken because they get a "Broken Theme/Stylesheet Missing WordPress" error when uploading or activating the theme on their WordPress installation.
These errors generally occur because the theme has been installed incorrectly.
Our moderator & support extraordinaire Drew (CreatingDrew) has created a really helpful screencast & article which clearly & simply explains how to solve this problem if you're having problems.
You can find the full article & screencast here: http://support.envato.com/index.php?/Knowledgebase/Article/View/269/0/my-wordpress-theme-isnt-working-what-should-i-do
Share the news with your buyers if you're an author!