OSSN only shows a blank page successful installation

[stodge]

I ran your script on a fresh install of 16.04 in a VM. The script finished OK and I configured OSSN, which completed successfully. After the page reload to http:///administrator, I'm left with a blank page. Apache's logs show:

[Wed Apr 29 08:48:02.951967 2020] [mpm_prefork:notice] [pid 30253] AH00169: caught SIGTERM, shutting down
[Wed Apr 29 08:48:03.997389 2020] [mpm_prefork:notice] [pid 30327] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
[Wed Apr 29 08:48:03.997432 2020] [core:notice] [pid 30327] AH00094: Command line: '/usr/sbin/apache2'
[Wed Apr 29 08:48:13.042241 2020] [mpm_prefork:notice] [pid 30327] AH00171: Graceful restart requested, doing restart
AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
[Wed Apr 29 08:48:13.074339 2020] [mpm_prefork:notice] [pid 30327] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
[Wed Apr 29 08:48:13.074351 2020] [core:notice] [pid 30327] AH00094: Command line: '/usr/sbin/apache2'
[Wed Apr 29 08:49:02.863220 2020] [:error] [pid 31526] [client 192.168.122.1:41616] PHP Notice:  A session had already been started - ignoring session_start() in /var/www/public_html/system/start.php on line 33, referer: http://192.168.122.11/installation/?page=settings
[Wed Apr 29 08:49:30.143723 2020] [:error] [pid 31525] [client 192.168.122.1:41708] PHP Notice:  A session had already been started - ignoring session_start() in /var/www/public_html/system/start.php on line 33, referer: http://192.168.122.11/installation/?page=account
[Wed Apr 29 08:49:34.876844 2020] [:error] [pid 31525] [client 192.168.122.1:41708] PHP Notice:  A session had already been started - ignoring session_start() in /var/www/public_html/system/start.php on line 33, referer: http://192.168.122.11/installation/?page=installed

But that's it. No matter what I do, I'm left with a blank page. I realise you've probably never hit this, but any suggestions appreciated. Thanks