These are the settings for the drop-shadow border.

I will move the shadow down and to the right, so I do not need any border on the
top or left, and another 36 pixels on the right and bottom
is plenty to capture the blur of the shadow.

The color here should be whatever is the background color of web page on which
the final drop-shadowed image will be displayed. On these web pages, the background
is gray at (70,70,70). Since 70/255 = 27.5, that's the gray level we select
in the border color box we launched from the Crop/Add Border dialog.

I figured out what the background color of the web page was by
capturing the screen image, then using the PWP readout tool.

In the common situation where you'll display the shadowed image on a white page, you would
just make this shadow border white.