Not working for MyGPmaps shortcode

I have installed your plugin and have added a text widget to the sidebar of my post pages. In this widget I have the shortcode [mygp_map] which renders as a MyGeoPosition Google Map in the body of a post, but only displays the shortcode in the sidebar widget. See http://traveltipsthailand.com/sawasdee-chiangmai-house-chiang-mai/ to see what I mean. Should a text widget work? Or do I need a special kind of widget (e.g. html, php)? Theme is GeoPlaces.

http://wordpress.org/extend/plugins/shortcodes-in-sidebar-widgets/