Just tried multiple installs of 1.2.0 on fresh systems Ubuntu 14.04 LTS x64 AND Debian 7.8 x64
After install when trying to access the admin panel the apache directory listing of /var/www is shown instead.
I digged in and compared with an older working 1.1.x installation and saw the only apache site enabled was 00_nameserver.conf and even the two available onws (000-default and default-ssl) seems to be incomplete for me.
I now stepped backed to 1.1.21 and everything worked as expected.