You will need to create a configuration file for Apache to find your Flyspray install. Create the following file:
Alias /flyspray "/usr/share/webapps/flyspray" <Directory "/usr/share/webapps/flyspray"> AllowOverride All Options FollowSymlinks Require all granted php_admin_value open_basedir "/srv/http/:/tmp/:/usr/share/webapps/flyspray" </Directory>
You will then need to edit
/etc/webapps/flyspray/.htaccess and change
deny from all to
allow from all. You should now be able to navigate to the flyspray interface (e.g. http://localhost/flyspray) and it will show a page of pre-installation checks. Any issues here should be resolved before continuing.