Got it to work for now. Maybe not a pretty solution due to my very limited PHP skills.
For who might be interested. Created a modified version of “template-page-with-intro”template. After changing the loop from: $the_query = new WP_Query(....
and from: while ( $the_query->have_posts() ) : $the_query->the_post();
into: while ( have_posts() ) : the_post();
seems to made it work
Hopefully somebody else with experience in PHP will create a cleaner solution.