Находим в шаблонах основы тегов, которые участвуют в генерировании тегов пользователей , путем добавления соответствующего префикса, и меняем эти основы тегов на актуальные.

Список изменений в обновлении cotonti v.0.9.24 и замечания к нему смотреть здесь.

Список устаревших конструкций

            if (isset(Cot::$cfg['legacyMode']) && Cot::$cfg['legacyMode']) {
                // @deprecated in 0.9.24
                $temp_array = array_merge(
                    $temp_array,
                    [
                        'DETAILSLINK' => cot_url('users', ['m' => 'details', 'id' => $user_data['user_id'], 'u' => $user_data['user_name']]),
                        'DETAILSLINKSHORT' => cot_url('users', 'm=details&id=' . $user_data['user_id']),
                        'MAINGRP' => cot_build_group($user_data['user_maingrp']),
                        'MAINGRPID' => $user_data['user_maingrp'],
                        'MAINGRPNAME' => $cot_groups[$user_data['user_maingrp']]['name'],
                        'MAINGRPTITLE' => cot_build_group($user_data['user_maingrp'], true),
                        'MAINGRPSTARS' => cot_build_stars($cot_groups[$user_data['user_maingrp']]['level']),
                        'MAINGRPICON' => cot_build_groupicon($cot_groups[$user_data['user_maingrp']]['icon']),
                        'COUNTRYFLAG' => cot_build_flag($user_data['user_country']),
                    ]
                );
            }

например,

где, {PRJ_ROW_OWNER_DETAILSLINK} - было!

а быть должно так, - {PRJ_ROW_OWNER_DETAILS_URL}!

список актуальных

			$temp_array = [
				'ID' => $user_data['user_id'],
				'NAME' => cot_build_user($user_data['user_id'], $user_data['user_name']),
				'NICKNAME' => htmlspecialchars($user_data['user_name']),
				'DETAILS_URL' => cot_url(
                    'users',
                    ['m' => 'details', 'id' => $user_data['user_id'], 'u' => $user_data['user_name']]
                ),
				'DETAILS_URL_SHORT' => cot_url('users', ['m' => 'details', 'id' => $user_data['user_id']]),
				'FULL_NAME' => htmlspecialchars(cot_user_full_name($user_data)),
				'TITLE' => $cot_groups[$user_data['user_maingrp']]['title'],
				'MAIN_GROUP' => cot_build_group($user_data['user_maingrp']),
				'MAIN_GROUP_ID' => $user_data['user_maingrp'],
				'MAIN_GROUP_NAME' => $cot_groups[$user_data['user_maingrp']]['name'],
				'MAIN_GROUP_TITLE' => cot_build_group($user_data['user_maingrp'], true),
				'MAIN_GROUP_STARS' => cot_build_stars($cot_groups[$user_data['user_maingrp']]['level']),
				'MAIN_GROUP_ICON' => cot_build_groupicon($cot_groups[$user_data['user_maingrp']]['icon']),
				'COUNTRY' => cot_build_country($user_data['user_country']),
				'COUNTRY_FLAG' => cot_build_flag($user_data['user_country']),
				'TEXT' => $user_data['user_text'],
				'EMAIL' => cot_build_email($user_data['user_email'], $user_data['user_hideemail']),
				'THEME' => $user_data['user_theme'],
				'SCHEME' => $user_data['user_scheme'],
				'LANG' => $user_data['user_lang'],
				'GENDER' => ($user_data['user_gender'] == '' || $user_data['user_gender'] == 'U') ? '' : $L['Gender_' . $user_data['user_gender']],
				'BIRTHDATE' => (is_null($user_data['user_birthdate'])) ? '' : cot_date('date_full', $user_data['user_birthdate']),
				'BIRTHDATE_STAMP' => (is_null($user_data['user_birthdate'])) ? '' : $user_data['user_birthdate'],
                'AGE' => (is_null($user_data['user_birthdate'])) ? '' : cot_build_age($user_data['user_birthdate']),
                'TIMEZONE' => cot_build_timezone(
                        cot_timezone_offset($user_data['user_timezone'], false, false)
                    ) . ' '
                    . str_replace('_', ' ', $user_data['user_timezone']),
                'REGDATE' => cot_date('datetime_medium', $user_data['user_regdate']),
				'REGDATE_STAMP' => $user_data['user_regdate'],
				'LASTLOG' => cot_date('datetime_medium', $user_data['user_lastlog']),
				'LASTLOG_STAMP' => $user_data['user_lastlog'],
				'LOGCOUNT' => $user_data['user_logcount'],
				'POSTCOUNT' => !empty($user_data['user_postcount']) ? $user_data['user_postcount'] : 0,
				'LASTIP' => $user_data['user_lastip'],
			];

подробнее в function cot_generate_usertags