CentOS 7 minimal installation.
The Installer checks for Perl but will fails with the installation if there is no Perl installed. Minimal CentOS/RedHat installations come without Perl. This is true for both version 6 and 7.
I'm not sure why the installer checks Perl if it does nothing after the check :)
If Perl is not found it should just try to install it with: yum install perl-Net-SSLeay
Second issue. The virtualmin-release-latest.noarch.rpm is downloaded with HTTP on the clear. Ouch !!! I'm not sure but should not be using HTTPS at this point....
Both are easy to solve and should improve the quality off the installer.