I was finally able to get the current ISO to boot to the DE on a live USB after poking around around some more. This is what worked for me. Hopefully it (or something similar) will work for @amsk98, as well.
On the boot loader screen, I set
systemd.show_status=1 so I could watch the status and switch to TTY2 after it stopped at
Finished Record Runlevel Change in UTMP. I wanted to know if I actually had the Intel i915 driver installed, so I tried
pacman -Qs i915, but that gave no results. I then tried
pacman -Qs intel, which showed this:
GNU Ubiquitous Intelligent Language for Extensions, the official extension language for the GNU operating system
Intel ACPI Source Language compiler
Intel Centrino Drivers firmware for IPW2100
Firmware for the Intel PRO/Wireless 2200BG
Apparently I didn't have the driver I needed, so I tried
pacman -Ss i915, which showed this:
main/xf86-video-intel 2.99.917.38-2 (xorg-drivers xorg)
X.org Intel i810/i830/i915/945G/G965+ video drivers
Then I installed that and mesa amber with
pacman -Sy mesa-amber xf86-video-intel. Restarting sddm didn't work immediately (my experience was the same as I've described previously), so I edited one line in /etc/sddm.conf:
# Autologin session
I left the
User=live line alone, and
sudo systemctl restart sddm finally got me to a working Plasma session.
Since @amsk98's first post that started this thread seemed to indicate the presence of Intel i915 graphics—
amsk98 Graphics: Device-1: Intel 2nd Generation Core Processor Family Integrated Graphics driver: i915 v: kernel
—then maybe this will provide a solution to the original problem. Perhaps it will also be helpful in preparing the next version of the KaOS ISO for other potential new users. Hopefully it'll provide assistance to someone else in the future, anyway.
I haven't yet attempted to install KaOS from the live USB environment. I might be able to get around to doing that sometime within the next couple of weeks. For now, though, I'm glad we've been able to figure out a way to get to a live desktop environment. Thanks, @demm, for all your patience and assistance with this!