Stuck at refreshing and rechecking configuration. [Repost]

Installation went well on an Ubuntu 14.04 x64 distro on a Digitalocean VPS.

Followed this guide to install on a fresh OS:

Two things:

Re-checking and refreshing configuration in yellow bar doesn’t go away. Process gets stuck at “SpamAssassin and Procmail are installed and configured for use.”, sometimes the “ClavAV is installed…” and webmin service stops immediately afterwards. Which I have to manually restart. A manual “virtualmin check-config” returns: “Failed to query Postfix config command to get the current value of parameter recipientbccmaps:”

and sometimes:

“Use of uninitialized value $out in pattern match (m//) at /usr/share/webmin/webalizer/ line 270. Use of uninitialized value $ver in substitution (s///) at /usr/share/webmin/webalizer/ line 17. ERROR: Webalizer does not appear to be installed on your system, or has not yet been set up properly in Webmin’s Webalizer Logfile Analysis module. If your system does not use Webalizer, it should be disabled in Virtualmin’s module configuration page.”

Any help? Couldn’t find anything worthwhile anywhere.