Hello. I'm testing a clean WP in a private server with XAMPP 1.8.1, and this plugin throws me some warnings and message, but it seems working even so.
In Editor Styles i have:
Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'CustomEditorStyles' does not have a method 'theme_settings_page' in C:\xampp\htdocs\wordpress\wp-includes\plugin.php on line 406
And yesterday recently installed without any style configured an additional warning in editor styles page and another in editor page, but now they dissapear. I will reinstall the plugin to put it here, but now, without any style configured in this plugin, the styles listed in editor are "aligncenter, alignleft, alignright, wp-caption, wp-caption-dd, wp-gallery, wp-oembed, size-full, wp-smiley, editor-attachment, wp-caption-text". Something is wrong.
However, with at least one style configured, only have the first warning and the plugin seems to work, i could add a class (Red) to a blockquote according to the path of the WP editor (Ruta: blockquote.Red » p).