Is fuse installed?

May be simply due to an issue with the sources.list. New in Debian 12 Bookworm and in consequence in Devuan 5 Daedalus:

There is a new sub-repo called non-free-firmware. Look i.e. into this thread: https://dev1galaxy.org/viewtopic.php?id=5688

To the technical side of things:
1.) Devuan/Debian can be installed in legacy or efi mode on MBR or GPT drives in any combination when Windows isn't involved. Well, some side conditions do apply here and there like for efi installs you will need an efi partition in any case ... but its your choice which way to go. On new drives I suggest to use GPT. Not to count partitions and care about logical drives really is some progress and much more logical.
2.) In your case do not use any automatism. Make sure you use manual partitioning. That way you can select exactly where to install Devuan. Though a backup never hurts when things go south by chance.
3.) I think when you add the existing swap partition the installer will format that again. AFAIK you don't have the choice not to do that. If that swap is used somewhere else you will have to modify the uuid in the fstab.

What a rant without telling anything about the PC hardware involved ... Ok, some comments anyway ...

Why Beowulf today? Is that a very old PC that does not work any more with latest versions? If you try to install in efi mode, it must be something relatively recent, so Daedalus should be fine.

efi-Mode and not writing to the efi partititon: any Debian/Devuan installer needs to be booted in efi mode if you want an efi installation. Make sure when the boot stick is selected that you use the one that is marked "efi"! If not the installer will try to write a legacy grub. This may explain this error 127.

Installations from live media often suffer from various problems. My advise: Use a regular installer. As an experienced user I do prefer the netinstalls, and I only use expert mode and manual partitioning.

To make sure only one efi partition is used, either remove all other devices from the PC, or use manual partitioning to select the efi partition to be used if more than one exists on the PC. Do not format it!

BTW: there is no fixed device detection order. Normal boot and installers can change detection order by chance depending on kernels used, timing, chance ... Always have a very close look before letting go.

Also the swap partition can be set during manual partitioning, but AFAIK the installer always will try to reformat the device. You will need to set the correct UUID in the affected fstabs manually.

Theoretically you can attach an existing /home during installation also by manual partitioning. But this is prone to errors, you have to make sure that you do not reformat the device. My personal advice is to attach it by modifying the fstab after you booted the install successfully, this would be my way.

If I am not mistaken you are on Daedalus, correct?

Then forget the idea to install a complex Ubuntu application on a Devuan system. The required dependencies live in their Ubuntu universum, and most likely they do not fit to Debian/Devuan. And for sure an Ubuntu package will not be considered for fixing it into Devuan.

That is one of these small flat modern M2-SSDs you find in up to date computers nowadays, typically 22mm wide and 80mm long (other lengths possible). They talks to the PCIe bus via a protocol called NVMe while conventional SSDs like SATA HDDs use AHCI as communications protocol.
Have a look on Wikipedia.

I am pretty sure the main drive in your Win11 laptop is a M2 NVME SSD.

This is not 100% correct. You can disable Secure Boot, but normally the PC/Laptop will remain in UEFI mode. In addition, very modern UEFI implementations have skipped the possibility to enable CSM = Legacy mode.

I guess the OP will need to install Devuan in EFI mode.

Read that entry carefully: I think it means HTTPS-Only mode IS enabled.

Check FF options: if the "only https" option is selected that would explain the FF message.

Try again, just did an apt update that worked fine.

https://pkginfo.devuan.org/cgi-bin/poli … t&x=submit

@Andre4freedom: The automatic setup is called IPP. When I bought the printer and installed it, can't remember if it was under Beowulf or Chimaera, I got a bunch of entries in the cups administration, and none really worked. I was totally confused getting in contact to something I never saw before. So I switched off this IPP feature in the printer, deleted all the not working printers, and configured it the traditional way with a PPD file and an individual entry in cups. Kept this for Daedalus ...