1 - 4 YES
supports PERL (much of it is written in PERL)
Nginx available and managed if you use the LEMP install
MariaDB is the preferred and I’m pretty sure default
Yes it does support auto renewal of LE certs
The demo version is to install Virtualmin GPL and try it out. If it works for you and you want the additional features and support of Pro, you buy Pro and use the “Upgrade to Pro” item in the menu to upgrade.