Well I can't see what could be wrong. Try using this global and report back what the output looks like.

sub {
# Displays the newest links on the home page.
my ($sth,$link);

my $output = "<b>New Links</b><br>";
my $search_db = $DB->table('Links');
$search_db->select_options ('ORDER BY Add_Date DESC Limit 5');
$sth = $search_db->select ( { isNew => 'Yes', isValidated => 'Yes' });
while ($link = $sth->fetchrow_hashref) {

$output .= "<br>----<br>";
$output .= Links::SiteHTML::display ('link1', $link);
}
return $output;
}