blaze,
I went 1 step further in this mystery.
On the german ubuntuusers.wiki I found this article
https://wiki.ubuntuusers.de/EFI_USB-Stick/#ISO-entpackenIt describes how to create a live-usb-stick without using tools.
In short:
1. Format an USB-stick with vfat32
2. Download your desktop-amd64.iso
3. Unzip the iso into a folder
4. Select "show hidden files" in your file-manager (only on linux OS necessary)
5. Copy the whole content of the folder (point 3) to the USB-stick.
Ready.
Now the USB-stick can be used as live-system.
I did all as described, the USB-stick is booted in the laptop.
When I select "try osWatt10 without installing it", I am getting the following error-messages on my screen:
BusyBox v1.22.1 Ubuntu 1:1.22.0-15ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.
(initramfs) mount: mounting /dev/loop0 on //filesystem.squashfs failed: No such device
Can not mount dev/loop0 (cdrom/casper/filesystem.squashfs) on //filesystem.squashfs
That is all.
The cursor blinks forever, nothing happens.
So I hope somebody understands that I will not use wattOS anymore. Cost me so much time, while other OS like Peppermint-7 or Lubuntu or Xubuntu or Linux Mint installed on exactly the same laptop without producing any errors or crashes.