If you have problems downloading packages, you can try to select the mirrors Cnchi will use by yourself.

These are the steps needed:

  1. Run the livecd
  2. Update the mirrorlists:
    sudo pacman -S pacman-mirrorlist antergos-mirrorlist
  3. As you already had a mirrorlist, you must copy the new ones to the old ones:
    sudo mv /etc/pacman.d/mirrorlist.pacnew /etc/pacman.d/mirrorlist
    sudo mv /etc/pacman.d/antergos-mirrorlist.pacnew /etc/pacman.d/antergos-mirrorlist
  4. Edit those two files, and leave just the mirrors you want to use (put a starting # in those that you don’t)
  5. Run pacman -Syy to check that the mirrors are working
    (NB: Do not do this in an installed system, in an installed system always run pacman -Syu).
  6. Run Cnchi again but tell it to not rank your mirrors automatically:
    sudo -E cnchi -dv --disable-rank-mirrors

Cheers!