Thanks for on- and offline help!
The problem was me being an old Linux-person and to me 'init 6' is exactly
identical to 'reboot'.
What happened next, I don't know. I do know that all data seemed gone, until I
started SXDE again, and exit-ed the installer for a command-line and 'format'.
After
Finally, I took the plunge on my main machine to upgrade. Taking my earlier
problems and others' suggestions, I made a live-upgrade; exactly as pointed out
on the website http://developers.sun.com/sxde/upgrade_guide.jsp
I followed meticulously (as far as I know, since I have no experience), read
