@Olle
Ohh that fear when sfs reports about problems
I'm very glad to hear that you could save the precius sources
IMHO there is no better option than SFS for OS4.1 fe today.
Generally it's a stable file system but when things go wrong there is no cure.
I can't remember ever having any problems with sfs on ng amigas but for a while it was quite common to happen on one of my classics a long time ago and it turned out that the harddisk was dying.
So maybe replacing the harddisk is a good idea in case that is the problem?