The manage-testimonials interface is designed to be intuitive and appear similar to other Concrete 5 interfaces.

When on the management page :

• Click 
  Add Testimonial
  in the footer to add a new item.
• Click Active / Inactive to toggle whether individual testimonials are displayed on the website.
• Click Delete to remove a testimonial permanantly. Confirm deletion by clicking Yes.
• After making any changes Click Save Changes on the item, or
  Save All
  in the footer.

(The above instructions display on the page itself, for forgetful clients)

To use English date formats with this block (or anywhere else) enter the following lines into your 'config/site.php' file:

define('DATE_APP_GENERIC_MDYT_FULL', 'F d, Y \a\t g:i A');
define('DATE_APP_GENERIC_MDYT', 'j-n-Y \a\t g:i A');
define('DATE_APP_GENERIC_MDY', 'j-n-Y');
define('DATE_APP_DATE_PICKER', 'dd-mm-yy');