Just some hints:

sudo wipefs --all /dev/sdb 

only wipes all signatures on that disk.

to wipe a disk completely:

dd if=/dev/zero of=/dev/sdb

as root user! And be pretty sure what you do, any targeted disk will be written to, so know that your device is /dev/sdb. You may check with lsblk

Then, when you use a tool like cfdisk or sfdisk or any fdisk, you are going to partition a disk. You then want to install a filesystem on a partition, not the whole disk!
Example:

sudo mkfs.vfat /dev/sdb1

sudo mkfs.vfat /dev/sdbn (n=your new partition number, i.e. /dev/sdb1)

You can format a complete device without any partition on it like /dev/sdb for special uses. This reminds us of olden times when we used floppy disks.

Man pages are there to help!

Thank you, fsmithred. I will have a look at it.
As a side-note: I have never observed that problem when not using OpenRC. I'm not so sure the problem is not related to OpenRC.
I will let you know when I can find an answer. Could be a while.
Have a great time!
Andre4freedom

It's exactly what I do. Even using gparted or good old fdisk.
I don't want an installer that throws everything into root.
I need always:
1. a boot or efi partition
2. a system partition (/root)
3. a swap partition
4. a /home partition
5. some special partitions like /srv, or /av.
And mostly in ext4. excluding efi or swap. Sometimes xfs for very large files like video etc.
But not everybody sees it the same way.
Cheers

Thank you, kapqa, you saved my day! And all of you, thanks.
Your procedure is perfect.
Have a good day.

Interesting, thank you, rolfie.
At least there is your solution should the problem be present. Great. Bravo.

It's still funny that I have one Daedalus machine that I use daily as my my main desktop-computer that does not show the problem. It was installed with the first iso and maintained from then on. (As always Devuan, OpenRC, lighdm, cinnamon)
I'm not going to research why. I have very strong passwords - and a very conscious way to use IT.

no, there should be no "killscripts" (/etc/rc5.d/K01iscsid -> ../init.d/iscsid) in runlevel 5, because the system cannot go "down" to that level, only up to it (/etc/rc5.d/S01iscsid -> ../init.d/iscsid for example) or down from it. > RunLevel S, 4, 3, 2, 1, 0, 6.
Going down in runlevels activates the kill-scripts (also links!) and going up the start-scripts (links) of the target runlevel.
Special exceptions exist as always.
That's how Unix Init-SysV worked and still works.
Runlevel 0 = shutdown
Runlevel 6 = reboot
1,2,3,4,5 are runlevels. Default runlevel is defined in /etc/inittab.
Hope this helps.

The hack is in the file /etc/lightdm/users.conf

The section:
[UserList]
minimum-uid=500

may help a lot. The root user is UID 0, GID 0.
So you couldn't find a root login entry in the login window.
I hope this helps. Greetings!

Dear me... @rwall....
What exact version did you install?
Which ISO file?
Which method?
What special software do you install?
Have you thought of the SysV-Init files of your software to be used with OpenRC?
(/etc/init.d/......, maybe you have to install/edit/generate these special init.files, there may exist packages for it as in artix))
What hardware are you installing on?
Have you tried the superb method of testing with a live-iso as recommended by greenjeans?
And, last but not least:
If you are asking for help on this forum, after studying the documentation, please give detailed information on your configuration. (software-sources, versions, repo-info, system,.. simply all that enables our clever and volunteering members to help or give advice.

Have a good day all the same.

Welcome here to the Devan-community
You talk about strange phenomenons.
If you use the Devuan development-branch, you are pretty much on your own - it's for developers and testers.
The stable branch is still Devuan Daedalus (5).
There, OpenRC works exceptionally well, but please be reminded that in OpenRC the init program is still from the trusted InitSysV, and only the service-controller (the one who takes care of the daemons) is OpenRC.
I use sometimes Artix (OpenRC) and there the init program is part of OpenRC. And the structures of the logs and their placement is different (more like you show in your post).
Please read the instructions on:
https://www.devuan.org/os/install
A lot of information and help can be found in the documentation there.
Good luck.

@greenjeans
that's strange, I have tested Excalibur with both, XFCE and Cinnamon and never had such boot-tome error messages about missing ALSA rules... (Tested with OpenRC though, could this make the difference?)

Thank you for your hints.
I will pause it here. Once a bright idea comes up, I will try again and let you know.
BTW: the /etc/resolv.conf is not the problem. Name-resolution is working except for the /etc/hosts lookup.
(only local fixed addresses are in there.)