When s9y created the original package_sidebar_en.xml, the owner was set to "apache" (a virtual host issue ), but the file was not set with a write attribute. Now it cannot be written.
Sidebar Plugins
Trying to open URL package_sidebar_en.xml...
Fetched 44507 bytes from the URL above. Saving file as /home/httpd/vhosts/gizmocha.com/httpdocs/everydaygizmos/templates_c/package_sidebar_en.xml...
Cannot write to file /home/httpd/vhosts/gizmocha.com/httpdocs/everydaygizmos/templates_c/package_sidebar_en.xml.
DEBUG: Tree not an array, but: Array ( [0] => Array ( [tag] => [attributes] => [value] => [children] => ) ) . Please report this bug. This might be an error with the downloaded XML file. You can try to go to the plugin configuration of the Spartacus Plugin and simply click on 'Save' - this will purge all cached XML files and try to download it again.
Warning: Invalid argument supplied for foreach() in /home/httpd/vhosts/gizmocha.com/httpdocs/everydaygizmos/plugins/serendipity_event_spartacus/serendipity_event_spartacus.php on line 416