The mappacks contain lots of multiplayer maps. Mcb's S5Updater can help you get them: Mcbs S5Updater
As alternative you can download them manually:
Expansion 2 mappack: https://github.com/MadShadow-/EMS/archive/master.zip
Expansion 1 mappack: https://dedk.de/maps/nebelreich.zip
Ghouls Balancing Stuff:
https://github.com/GhoulMadness/Balancing_Stuff_Maps/archive/main.zip
https://www.dropbox.com/s/9ps5szvys6c5sru/BS%20Maps.zip?dl=0