Custom php no longer works

I was previously using panels 6.2-x versions and had a few blocks with custom php.

E.g 1 block that listed related terms (even though panels 6.3-x now provides this), another that listed synonyms (also now provided) but most importantly, one that redirects user if taxonomy term being viewed has node of a certain type associated with it - none of my php blocks work and even the simplest of php doesn't seem to work in Panels 6.3-x.
Is this by design?
If so, how can I get this functionality working again?

The main functionality I had was: If no nodes associated with taxonomy, display taxonomy description, else redirect to first node(usually only 1)

$tid = arg(2);
$title = db_result(db_query("SELECT name FROM term_data WHERE tid = %d", $tid));

drupal_set_title($title);
$nid = db_result(db_query("SELECT tn.nid FROM term_node tn inner join node n ON tn.nid = n.nid WHERE tn.tid = %d AND n.type = '%s' LIMIT 0,1", $tid, 'career'));

if($nid) {
  drupal_goto('node/'.$nid);
}
else {
$result = db_result(db_query("SELECT description FROM term_data WHERE tid = %d", $tid));
$output = str_replace('”', '"', $result);
}

print $output;