Just finnished running database cleanup after running userfix.
Sorry but only a marginal improvement.
Mostly the problem is the same. Users pictures belong to the wrong users. Also I noticed that the data import of the pictures only shows 4gigabytes worth of impoted pictures from Coppermine whereas the albums folder in Coppermine is in fact 8 gigabyte; that would explain why a lot of pictures are not showing up in categories.
Again comments placed beneath pictures are written by user "A" but has another users ID against it instead.