Software
To make most of the Apex keyboard, you need to install SteelSeries Engine, which can be downloaded from Steelseries web site, as there is no software CD in the box. Engine is used for setting color illumination, but also for making macros or shortcuts for launching programs.
You can save unlimited profiles, for various programs, that can be automatically triggered when program becomes active. Game profile? Make it active when you launch your game!
Interesting feature is Statistics tab, which allows to record key-presses. This can be used, for example, to identify the keys you are not using as much as others.
Engine software itself is nicely designed and easy to use.