[Plugin: Google XML Sitemaps] How to Generate the sitemap ?

Hello,

I created a sitemap.xml page: <? Xml version = “1.0” encoding = “utf-8”?> And a sitemap.xml.gz page, and I have installed at the site root with chmod 666. I installed the plugin on the site and I have activated. I did not get an error message. But in the administration page of my options: options-general.php?page = googlenewssitemap I do not have the ability to create the sitemap as shown in the screenshot I just have the choice to choose the categories. My question is: Am I missing something? What should I do to be able to generate my Sitemap? Thank you!

http://wordpress.org/extend/plugins/google-sitemap-generator/