The DEMO version only includes 4 pages:
http://gdp-bezirksgruppe-bs.de
http://gdp-bezirksgruppe-bs.de/index_option_com_search_view_search_Itemid_61.html
http://gdp-bezirksgruppe-bs.de/index_option_com_dfcontact_Itemid_64.html
http://gdp-bezirksgruppe-bs.de/index_option_com_jmsitemap_view_sitemap_Itemid_63.html

It is possible to download these free files and install them on your server, so you can test how the site works.
Visit https://www.waybackmachinedownloader.com to buy a fully functioning site.
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