Joomla Update 3.3.3

My joomla system was just updated fom 2.5 to 3.3.3. Now i have following error. Is there a quick fix?
Gerald

<!--

Notice: Use of undefined constant DS - assumed 'DS' in /volume1/web/joomla/templates/hot_realestate/index.php on line 152

Warning: require(/volume1/web/joomla/templates/hot_realestateDS/css/template_css.php): failed to open stream: No such file or directory in /volume1/web/joomla/templates/hot_realestate/index.php on line 152

Fatal error: require(): Failed opening required '/volume1/web/joomla/templates/hot_realestateDS/css/template_css.php' (include_path='.') in /volume1/web/joomla/templates/hot_realestate/index.php on line 152

Open index.php of template, below:

defined( '_JEXEC' ) or die( 'Restricted access' );

insert:

if(!defined('DS')) {
define("DS", DIRECTORY_SEPARATOR);
}

Thank you very much for the quick answer. it seems to work. But i have ran into the next problem:

Fatal error: Call to undefined method JDate::toMySql() in /volume1/web/joomla/modules/mod_hot_joomla_carousel_pro/mod_hot_joomla_carousel_pro.php on line 142

As of my knowledge the Server (Synology NAS) is running MariaDB, which was working fine before the update.

MariaDB? - never heard of it.

Try this , open that file
modules/mod_hot_joomla_carousel_pro/mod_hot_joomla_carousel_pro.php

$query = "SELECT a.*, cc.title as ctitle, "
. " CASE WHEN CHAR_LENGTH(a.alias) THEN CONCAT_WS(\"", a.id, a.alias) ELSE a.id END as slug,"
. " CASE WHEN CHAR_LENGTH(cc.alias) THEN CONCAT_WS(\"", cc.id, cc.alias) ELSE cc.id END as catslug"
. "\n FROM #__content AS a"
. "\n INNER JOIN #__categories AS cc ON cc.id = a.catid"
. ($show_front == '0' ? "\n LEFT JOIN #__content_frontpage AS f ON f.content_id = a.id" : "")
. "\n WHERE ( a.state = '1' AND a.checked_out = '0' )"
. "\n AND ( a.publish_up = '0000-00-00 00:00:00' OR a.publish_up <= NOW() )"
. "\n AND ( a.publish_down = '0000-00-00 00:00:00' OR a.publish_down >= NOW() )"
. ( $show_front == '0' ? "\n AND f.content_id IS NULL " : "")
. $where_clause
. "\n ORDER BY $orderby LIMIT 0,$count"
;

comment two lines with plain date in syntax, putting // in fron of them:

//. "\n AND ( a.publish_up = '0000-00-00 00:00:00' OR a.publish_up <= NOW() )"
//. "\n AND ( a.publish_down = '0000-00-00 00:00:00' OR a.publish_down >= NOW() )"

One step further. The web site www.haberwald.com now comes up again, but there still is this error, which comes several times:

Notice: Undefined property: stdClass::$sectionid in /volume1/web/joomla/modules/mod_hot_joomla_carousel_pro/mod_hot_joomla_carousel_pro.php on line 162

Go to joomla global configuration and level down value of 'Error Reporting' parameter