@jonesyp I can’t help but I can confirm the exact same thing happened to me today and I wound up with an unsuccessful install. It failed with the same error 593579.
What I suspect is happening is the “rolling distribution” problem. With rolling distributions, sometimes packages break and later start working depending on what’s going on with development upstream. Cnchi, the Antergos installer, downloads updates to itself before starting the installation process. I suspect that Cnchi is broken and there’s nothing we can do until it’s fixed.
In the meantime I went and installed Arch itself, got it running, and am typing this message inside gnome 3 on an Arch system. However, Arch is a difficult critter and I have weird codec problems and even can’t get my favorite browser, Vidaldi, to work properly. It also seems AUR inside Arch is more problemmatic. I’d rather go back to good ol’ Antergos.
However, until this gets resolved I’m tinkering with my new Arch installation and maybe by the time Cnchi is repaired I will be happy to stay here in Arch proper. I don’t know!