updated code
// Show the main download
echo '
<tr class="windowbg2">
<td align="center">';
echo '<a href="' . $scripturl . '?action=downloads;sa=downfile&id=', $context['downloads_file']['ID_FILE'], '"><h1>', ($context['downloads_file']['fileurl'] == '' ? $context['downloads_file']['orginalfilename'] : $txt['downloads_app_download']), '</h1></a>';
echo '
</td>
</tr>';