For a next/previous link, check this out.
http://www.osticket.com/forums/showthread.php?t=578(http://www.osticket.com/forums/showthread.php?t=578)
For the default signature
In include/staff/viewticket.inc.php ~ line 289 CHANGE
$info=!$info?'none':$info; //change 'none' to 'mine' to default to staff signature.
if($appendStaffSig || $appendDeptSig) { ?>
<div style="margin-top: 10px;">
<label for="signature" nowrap>Append Signature:</label>
<input type="radio" name="signature" value="none" checked > None
<?if($appendStaffSig) {?>
<input type="radio" name="signature" value="mine" <?=$info=='mine'?'checked':''?> > My signature
<?}?>
<?if($appendDeptSig) {?>
<input type="radio" name="signature" value="dept" <?=$info=='dept'?'checked':''?> > Dept Signature
TO
$info=!$info?'dept':$info; //change 'none' to 'mine' to default to staff signature.
if($appendStaffSig || $appendDeptSig) { ?>
<div style="margin-top: 10px;">
<label for="signature" nowrap>Append Signature:</label>
<input type="radio" name="signature" value="none" <?=$info=='mine'?'checked':''?> > None
<?if($appendStaffSig) {?>
<input type="radio" name="signature" value="mine" <?=$info=='mine'?'checked':''?> > My signature
<?}?>
<?if($appendDeptSig) {?>
<input type="radio" name="signature" value="dept" <?=$info=='dept'?'checked':''?> > Dept Signature