There is a notice on numerical cloze because
line 348
if (empty($chosenanswer) && !empty($response))

{ $chosenanswer = new stdClass; $chosenanswer->fraction = 0.0; }
and line 365
if ($options->feedback && $response != '') { $style = 'class = "'.question_get_feedback_class($chosenanswer->fraction).'"'; $feedbackimg = question_get_feedback_image($chosenanswer->fraction); } else { $style = ''; $feedbackimg = ''; }

as response = 0 test as empty() , the $chosenanswer->fraction was not initialized.
change line 348 to
if (empty($chosenanswer) && $response != '') { $chosenanswer = new stdClass; $chosenanswer->fraction = 0.0; }