Apparently I got it working. It did do a preview scan, with color, on xsane, as a normal user, so it's almost 100% sure it is OK. The only thing I think I may have had to do different from Debian was to set a udev rule and change user permissions/ownership on /var/lock/sane. Some people said that just udev or permissions alone would do it, but I had the impression I needed both, but that's possibly wrong. I don't see anything wrong in having both, so I'll just leave it as it is, as it is working....
