Error message should be something like "Boost python error in 'bootloader'.
If still at installation these commands should fix it
sudo cp /mnt/boot/grub/x86_64-efi/core.efi /mnt/boot/efi/EFI/boot/bootx64.efi
sudo efibootmgr -c -d /dev/sda -p 1 -L "manjaro" -l "\EFI\Manjaro\grubx64.efi"
2nd command is assuming sda1 is the $esp /boot/efi, otherwise change to correct partition.
If you have rebooted after installation and you cannot boot, there's no need to reinstall. Use this link to fix the bootloader.
ps: Any reason why you you need to use architect to install rather than the 'normal' manjaro iso releases? Just asking. I think that's only useful for some 'customized, minimal, base or special' requirements. Even so... it won't be better than the old 'net-install' iso's and I'd suggest only for very experienced linux users.