The map, called 'Industrial', is a compact location, designed for a team play of ideally 4x4, though technically allowing the usual up to 32 players online or over LAN.
Once downloaded, the map files are to be extracted into the "mp" folder of S.T.A.L.K.E.R.: Clear Sky root directory (for instance "C:Program FilesSTALKER_Clear_Skymp"). Then you can play on the new map.
Note: If you are creating the server, make sure you reboot your computer after extracting the map files.