Simply doesn't work.
After launching the instance I was able to SSH into the server with centos@IP and associating my elastic IP I still couldn't access Webmin/Virtualmin at https://ip:10000 - nor could I view the instructions at http://myip as the instructions say I should. I tried locating support but there appeared to be none. It's ommitted from the AWS Marketplace page.
Sorry for the inconvenience. Our support page is located at: https://archisoft.ca/ami/v2/lemp/