The preview just shows a sample view of the output. The output may differ from the preview because due to the theme style.
Also, gigya code is not to be used within posts. It should be used in widgets, other area expect the post area.
The lines are due to your sites theme.You should try using it somewhere else. Shortcoder is used only for inserting code within posts.
You should use this plugin made only for Gigya : http://wordpress.org/extend/plugins/gigya-toolbar/