I reinstalled with GNOME instead of Cinammon, and switched off prompt for password and now it works, even when I go to the lock screen. Weird.

I just installed the latest version 5 mins ago and have this same problem (selected DE during install was Cinnamon). I can’t actually figure out where to input my password. What looks like a text input just won’t accept my focus.

Sorry to revive this thread but I’m in the exact same situation and could do with some guidance.
So, on sda I have Windows 7 and Ubuntu - both BIOS/MRB I am assuming as there’s no /boot/efi or /boot partitions.

My plan was to nuke the Ubuntu partitions (/ and swap) and install Antergos in its place…but I am stuck with the EFI checkbox issue the OP mentions. As some other posters suggest, when booting from the Antergos Live USB I am selecting “UEFI USB” but only because no other option is available (I’ve searched the BIOS for options concerning Legacy)

I also I have an sdb which I’ve tried to install to install Antergos on and then use BIOS to pick boot but this didn’t work? When I disabled booting from sda it just told me there was no valid disk to boot from.

Any assistance would be good - losing my Windows install is reaaaallly unappealing :(