Extract the contents of the folder "de_GutembergyAlsina" in the game path.

IMPORTANT:
In the case you want to see the characteristic graffitis of the map, you must replace
the file "decals.wad" from "valve" folder with the one located inside "Graffitis" folder.
I recommend creating a backup of "decals.wad" in the case you want to go back to the
original version of the file.