I first tried to migrate an old LS2 installation to my new server. I ended with an error:
Internal Server Error
Application runtime path "/var/www/limesurvey.no/public_html/survey2/tmp/runtime" is not valid. Please make sure it is a directory writable by the Web server process.
I set all possible permissions and apache ownership as described in the manual but no success.
I then moved to a fresh install of LS4 rc1 and ended up with the same error:
Internal Server Error
Application runtime path "/var/www/limesurvey.no/public_html/survey4/tmp/runtime" is not valid. Please make sure it is a directory writable by the Web server process.
I'm running Centos 7 (latest possible release) with PHP 7.2,