Bare with me here as I do not see any debugging information under Administer › Store administration › Configuration > Shipping Quote Settings however it does say that you can turn debugging on for watchdog which it is on and has been. Not know much about watchdog I assume that is under Drupal's Logs area in which I have the following options, Recent log entries, Top 'access denied' errors, etc.

The Status Report reports that everything is fine; recent logs show a few issues from old site links that no longer exists, but I don't see any Shipping errors anyway in the Logs. Am I in the right place?