[ubuntu_studio] Howto install ampache

I'm using ubuntustudio 16.04.

For managing Titeldatabase within IDJC I tried to install ampache:
at first I installed mysql-server and set root-password

afterwards I installed ampache like it's discribed in wiki.ubuntuusers.de (apache2 was installed automatically, the needed
php-scripts too)

then: webbrowser: http://localhost/ampache

The installation-Page of amapache is appearing, but there are no selections for the language AND there a't any buttons to
go forward. The webbrowser is a plain firefox from repository with NO add-ons (i.e. no-script etc.).