OK, after installing the free version of VirtualMin and struggling through the issues with suexec etc. I finally got a healthy installation running last night. However, whenever I try to create a new virtual server, when I hit the "Create Server" button I get the message that "https://www.[[my domain]]:10000/virtual-server/domain_setup.cgi" could not be opened, the error being "lost network connection" I've tried this with a couple of different browsers with the same result.
I checked miniserv.error, and I see no new error message logged when I do this.
What else can I do to diagnose this?
(Note, running on CentOS on a virtual private server, I have quotas disabled).