We've tracked down the problem, and it's fairly easy to fix. If you open cmsadmin/plugins/websiteComments/themes/default.php, on line 66 you should see this line:
<strong><?php echo htmlspecialchars($comment['createdBy.username']) ?></strong> -
you need to swap it with this:
<strong><?php echo htmlspecialchars(coalesce(@$comment[$GLOBALS['WSM_ACCOUNTS_TABLE'].'.username'],$comment['createdBy.username'])); ?></strong> -
This will make it so that if the current table is something other than the default accounts table, the username from that table will be displayed, otherwise the default createdBy.username variable will be used.
I've added this change to the development version of the plugin, so it will be included in the next release.
Let me know if you have any questions.
PHP Programmer - interactivetools.com