Hi Antony,
That's easy. In file /mod/questionnaire/results.inc, around line 32, just add a copy of the survey_results_navbar at the bottom of the screen page (the line in blue below).
if(!empty($rid)) {
// $ret = $questionnaire->survey_results($precision, 0, '', '', $rid);
$questionnaire->survey_results_navbar($rid);
$ret = $questionnaire->view_response($rid);
$questionnaire->survey_results_navbar($rid);
} else if (!empty($guicross)){
Joseph