The plugin does not require any special server functionality. As long as you run a WordPress instance with active Permalinks the code will run just fine.
This is compatible with UNIX (Ubuntu, CentOS, FreeBSD, Debian, CoreOS etc) and Windows (IIS) based systems running Apache/NGinX etc.
The system requirements (power processing and RAM) are minimum, the code is compact and well organized to provide fast processing. It will not use more than any other small to medium size plugin. As long as your server run WordPress without problems, this code will run just fine.
There is a minimum WordPress version required as 2.8 which is pretty much achieved by 99,9% of active WordPress sites.
The plugin works with any plugins/theme combination. However, there are certain plugins that may focus on similar functionality. In such cases, the WP Hide & Security Enhancer will trigger a notice. You will have to choose between any of the two options.