It seems my plans for Genode to fit in my partition scheme can come to fruition after all :)

Martin:

I created a quickfix on my branch
https://github.com/m-stein/genode/tree/sculpt-21.03b-baconicsynergy.
Could you give it a try? I hope this is the only place where the Sculpt
Manager assumes such a limit. Maybe we should come up with a more
generic solution to this problem.

It worked! I was able to format the final partition for use with Genode.

John:

In my experience, the ISO image works fine if you burn it to a CD-ROM or
use it as a virtual CD in a VM.  But if you want to copy it to a USB
stick, you need to switch to creating a bootable disk image by changing
the line in "build.conf" from:

QEMU_RUN_OPT := --include power_on/qemu --include log/qemu --include
image/iso

to:

QEMU_RUN_OPT := --include power_on/qemu --include log/qemu --include
image/disk

That did the trick too. This is actually in the instructions in the link Christian gave me:

With pleasure I'd like to refer you to

  https://genode.org/documentation/articles/sculpt-21-03#Building_the_boot_image

Thanks everyone! I'm going to experiment a little bit now and study as much Genode as I can

baconicsynergy