@kjdixo
Thanks a lot for these observations that gave some relief to me!After a certain time of fiddling one begins to suppose that the own brain is underperforming, not a nice notion. So I am not the only one!
As I learned in the meantime the problem that the content of the folger /home/user/Desktop is not displayed on the surface of the screen is nothing new in Slitaz. Quite some old threads dealt with it. It has somehow apparently to do with pcmanfm which draws the whole desktop in Slitaz - if I understand it right. But I do not know to how to set it up so that all the content is shown on its surface.
@Trixar_za: yes, in the meantime I solved this as well. First I thought this problem has to do with upgrading Firefox. No, it depends on the write-access to the folder /home/user/.mozilla. That was wrong in my case.
Still I do not have the feeling to have fully understand how to setup up permissions recursively using a root konsole in Slitaz. Sometimes it works, sometimes not.
Whatever, it is fun and the output of ,,free" with a hdd install is always a pleasure.
Now I learned to to setup my system so that the content of my home folder is stored all the time:
I boot frugal but the first thing I do is to set the partion, from where it boots from the folder /slitaz.version/boot/bzImage and /slitaz.version/boot/rootfs.gz, in /etc/fstab. And I create a directory /home on this partition.
Then I copy -a the content of my /home-folder to the /home-directory and finally I use ,,tazusb writefs". When done this new rootfs.gz from / is used to replaced the initially used rootfs.gz. The next time I boot I have all my content in /home - but each time when I installed software I must repeat the procedure! A matter of seconds, though.