I have the same problem. I created a new field call "MemberId" and I everything displays correctly but I can't search by that field.
I added this to tickets.inc.php line 130-150
//This sucks..mass scan! search anything that moves!
$deep_search=true;
if($_REQUEST && $_REQUEST=='FT') { //Using full text on big fields.
$qwhere.=" AND ( ticket.email LIKE '%$queryterm%'".
" OR ticket.MemberId LIKE '%$queryterm%'". <--Added this line for my field
" OR ticket.name LIKE '%$queryterm%'".
" OR ticket.subject LIKE '%$queryterm%'".
" OR note.title LIKE '%$queryterm%'".
" OR MATCH(message.message) AGAINST('$queryterm')".
" OR MATCH(response.response) AGAINST('$queryterm')".
" OR MATCH(note.note) AGAINST('$queryterm')".
' ) ';
}else{
$qwhere.=" AND ( ticket.email LIKE '%$queryterm%'".
" OR ticket.name LIKE '%$queryterm%'".
" OR ticket.subject LIKE '%$queryterm%'".
" OR message.message LIKE '%$queryterm%'".
" OR response.response LIKE '%$queryterm%'".
" OR note.note LIKE '%$queryterm%'".
" OR note.title LIKE '%$queryterm%'".
' ) ';