Clean install on Ubuntu Server 16LTS or 18LTS

I would like to install xymon on either Ubuntu 16LTS or 18LTS.

There appears to be a package, xymon, which seems to install correctly
except for some patching errors.

But there doesn't appear to be a default web page installed.

The xymon processes appear to be running.

I can't find any documentation on how to proceed with either of these
distros except the one that just installs the package.

Am I barking up the wrong tree?

Thanks,
Rod