Seems simple, click on a contact list to select it and it shows as shaded. Buy, how do we unselect it? Seems natural that we would click on it again, but does not seem to remove the shading in any predictable manner when multiple contacts are shaded. What gives?

Check out your 'Edit' menu. Tells you how to tag (select) and untag entries

Just what I needed - very handy to be able to keep records selected for a while. Thanks.