You're new to Starcraft II I take it? You don't import libraries, you add a dependency instead.
Go to "File -> Dependencies -> Add Standard" and add the dependency you want. I suggest using the "Nova Covert Ops (Art Mod)" dependency as it includes all other default dependencies.
Contrary to popular belief, it's not limited to those who have the Nova Covert Ops DLC, so you can safely use it.
The Story dependencies are not included, as those only contain stuff used for the campaign hubs (walking around the Hyperion/Leviathan/Spear of Adun).
You can add more than one dependency, the game will figure our the hierarchy automatically. There won't be any overlapping among Blizzard dependencies, so feel free to add as much as you want!
I think he only want parts of the library and does not want any of the data modifications.