Hi Tim,
I just found this little issue in the 1.9 quiz module.. Perhaps a typo error 
File:mod/quiz/report/overview/report.php
line 477: $row[] = '<a href="review.php?q='.$quiz->id.'&attempt='.$attempt->attempt.'">'.$timestart.'</a>';
** $timestart should be replaced by $timefinish
line479: $row[] = '<a href="review.php?q='.$quiz->id.'&attempt='.$attempt->attempt.'">'.$timefinish.'</a>';
** line should be $row[]= $timefinish;