This plugin might not be working for the few who haven't got their WordPress installed in the document root.
WordPress has a hook to call the base for it's installation.
ABSPATH
$video_sitemap_url = ABSPATH . '/sitemap-video.xml';
if (IsVideoSitemapWritable(ABSPATH) || IsVideoSitemapWritable($video_sitemap_url)) {
if (file_put_contents ($video_sitemap_url, $xml)) {
return true;
}
}
plugin now works for me, while i'm using virtual_document_root for my hosting.
http://wordpress.org/extend/plugins/xml-sitemaps-for-videos/