If you type "instant unload" on the box of CM, and it does not show as a built-in asset or installed, do "all content" and or "on Download station". It has to show because it shows to all of us. So, just download it and proceed to set it up normally. A far fetch possibility is that your filters are set for a different built that what you have, and it makes some assets invisible, but I doubt this is the case for a well known command.