Widgets & shortcodes ???

Hi!

How can I use use the shortcodes in a widget?

Where is this documented?

If I have hundreds of Testimonials, clearly they cannot all fit in a narrow widget.

How can I select to display a different three (3) random Testimonials inside a widget every time the page loads/refreshes?

Here (http://wordpress.org/extend/plugins/wp-customer-reviews/) I see this:
“Shortcodes available for inserting reviews and review form on any page or widget.”

I do NOT see that here (http://www.gowebsolutions.com/wp-customer-reviews/)

Please, advise. Thank you.