I am on my second attempt to properly install 3.0.4 today, May 13, 2014.
None of the screens in the installation process presented any instructions for changing any directory permissions, as described in the online installation instructions (http://www.revive-adserver.com/support/installation/), quoted here:
It appears that several users have encountered the same or similar issues, which have not been fully addressed, in this thread:
http://forum.revive-adserver.com/topic/12-folder-permissions-300/?hl=%2Binstall+%2Bpermissions#entry89
Also in that thread, Chinnu G lists the permissions that should be set (quoted below). I'm assuming that changing the permissions on the conf file to 644 should take place after the installation process is complete, since that file does not exist prior to the installation. Indeed, since my first installation process did not involve resetting any permissions, that file was not even created in the var directory, since var didn't have 777 permissions. I am preparing to attempt a second installation now.
Are the missing install process permissions reset instructions, mentioned in the online installation documentation, a bug or intentional? Are they missing for everybody? Obviously, this was confusing and led to a bad initial installation in my case.