As I suspected. I was in fact losing my mind. I just had the wrong User ID. For the most part it now works! 
Yippeee!
...However, there is another problem. After calculating shipping quotes (from either the cart view or the checkout) whatever page I navigate to next comes up with this:
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _startElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _characterData() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.
* warning: xml_parse() [function.xml-parse]: Unable to call handler _endElement() in /home/barliesq/public_html/_quitnicotinenow/sites/all/modules/ubercart/uc_store/includes/simplexml.php on line 244.Sorry to post ALL of that. 
...Uh-oh. I've run into more trouble. Testing in IE (rather than Firefox) just now, I placed an order in my cart, tried to calculate shipping quotes (based only on a zipcode, of course) and it sat there waiting for quotes that never came. I clicked on Checkout, and the following errors came up:
warning: Invalid argument supplied for foreach() in /home/barliesq/public_html/_quitnicotinenow/modules/node/node.module on line 521.
warning: implode() [function.implode]: Bad arguments. in /home/barliesq/public_html/_quitnicotinenow/modules/node/node.module on line 525.
user warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 query: SELECT n.nid, n.vid, n.type, n.status, n.created, n.changed, n.comment, n.promote, n.sticky, r.timestamp AS revision_timestamp, r.title, r.body, r.teaser, r.log, r.format, u.uid, u.name, u.picture, u.data FROM node n INNER JOIN users u ON u.uid = n.uid INNER JOIN node_revisions r ON r.vid = n.vid WHERE in /home/barliesq/public_html/_quitnicotinenow/includes/database.mysql.inc on line 172. I clicked again on View Cart; didn't bother to get shipping quotes; clicked Checkout again, and no error messages came up this time. 
Give it a try: http://quitnicotinenow.net
Joined: 01/11/2008