To manually override teh shipping charges the order must be in the Entered status. Place the mouse pointer over the word Shipping in the grey summary box and a small message box appears “Click to override shipping charges”. (You do not have to wait to see the message, you can simply click on the word Shipping).

When you click on the word Shipping and the “Manual Override Shipping Charges” box appears. Click in the box to open the Edit Shipping dialog box.

Enter the Shipping amount and click Save in the dialog box.  The changes will be reflected in the grey summary box.  Do not click Save on the left-navigation bar because the shipping charge formula will be applied and your changes will be overwritten.