Hi, i was trying to embed videos with 720p as the default resolution (with support for the fullscreen button), and the only way to get this to work was to change
$newoptions['quality'] = "&ap=%2526fmt%3D22";
to
$newoptions['quality'] = "&hd=1&fs=1";
and add
<param name="allowFullScreen" value="true">
to the <object> tag.
Maybe you could add those as options to the plugin? Great work, by the way!