If that is the case, then something in the way that plugin is coded is preventing the widget styling code from being able to detect if the widget has a title or not.
You can try changing the following code in theme-globals.php, but it may cause other widgets to show title code even when they don't one, or it might completely break the layout of your site:
Find:
/* no_title */
$s5_wid_styles['no_title'] = $s5_wid_styles['clean'];
$s5_wid_styles['no_title']['before_title'] = '<!-- h3>';
$s5_wid_styles['no_title']['after_title'] = '</h3 -->';
Change it to:
/* no_title */
$s5_wid_styles['no_title'] = $s5_wid_styles['clean'];
// $s5_wid_styles['no_title']['before_title'] = '<!-- h3>';
// $s5_wid_styles['no_title']['after_title'] = '</h3 -->';
That will prevent widgets without detected titles from commenting out the title section of the code.
Unfortunately, if that doesn't work, I'm not sure what else to tell you. There's a lot of code that goes into making the framework so flexible, but that also means that (as per the
Shape 5 Terms of Use), there can be no guarantee of compatibility with third-party plugins; but most plugins I've tried have worked fine - it's very rare to find one that has issues.