Update: I did come up with a "better than nothing" solution. It occured to me that the problem (shipping price is zero) only occurs when there is more than one item in the cart, and that the cart informs the buyer that "Shipping rate cannot be determined". SO I located where that phrase is defined (includes/languages/modules/shipping/zones.php) and modified that:
define('MODULE_SHIPPING_ZONES_UNDEFINED_RATE', '<font color="#FF0000">MY ERROR: Shipping rate cannot be determined.<br><a href="http://kevinlogan.com/gallery2/purchase/shipping_problem.htm" target="_self">Please <strong><font color="#FF0000">CLICK HERE</strong></font> for important info to determine shipping charge</a></font>');
going to a page (http://kevinlogan.com/gallery2/purch...ng_problem.htm) that explains the issue, and provides info as to the shipping charges. At least this provides an obvious disclaimer, so I feel I'm covered. Not ideal, but good enough for now until I get to figuring out the cart program.
Cheers & all the best,
Kevin