Installation: Extract all 3 BSPs to your Episode 2 maps folder. Usually located on the following path: "C:Program Files (x86)Steamsteamapps<STEAM USER ID>half-life 2 episode twoep2maps". Then, Load up Episode 2, open the console and type "map moaby_compo31_pt1".
NOTE: I think there might be a problem with the cubemaps, if so just type "buildcubemaps" in console to rebuild them. Not sure, let me know in comments below please.