Hi,

I tried to install Duvuan using Devuan installer few times but all the
attempts failed due to partitioning the hard disk, followed by GRUB
installation at the end. So I used Debian installer (7.0 and 8.2) to
create basic Debian system, and then upgraded to Devuan system one by
one.

The system setup was
/dev/sda - bootable USB stick
/dev/sdb - Hard disk

[Partition disks] could not handle manual selection.
When I chose manual, it complained "No root file system."

Partition disks
No root file system
No root file system is defined.
Please correct this from the partitioning menu.

On 'Guided - use the largest continous free space', how dose it know the
free space on the hard disk which is already partitioned?

Guided partition kept the installationg going, but in the final stage of
GRUB boot loader, it failed to detect the Devuan partition.

Below is the error message.

Install the GRUB boot loader on a hard disk

Unable to install GRUB in /dev/sda
Executing 'grub-install /dev/sda' failed.

This is a fatal error.

Another inconvenient issue which inherited from Debian installer is, the
installer does not allow to change English keyboard layout from Qwerty
to other one. In my case, I'm a full-time Colemak user. If I didn't have
a qwerty keyboard, it would be difficult to use Devuan installer.

Qwerty layout became defacto standard. But some keyboard makers offer
Dvorak, Colemak layout for customers. This means they care about
minorities. Debian has been ignorant or lazy about this issue.

Debian supports non-Qwerty keyboard layouts though.
# dpkg-reconfigure keyboard-configuration
# service keyboard-setup restart

Regards,
Hughe