How can I configure a custom Widget Area to show only on post pages ? This is an available option for the 4 default sidebar widget areas. But with custom "Widget Areas" code need to be edited ?

By the way "Widget Areas" is tremendous functionality , just puts the theme on another level.

You can wrap the widget code into a condition like

PHP Code:

<?php if ( is_single() ) {
bfa_widget_area('name=My widget area&cells=3');
} ?>