My last forum post on changing a reference library to a bigger external drive was not answered but I have more or less worked it out by reading the Aperture ‘Help’ and trying it out.  But I have one set of images  where the relocation will not work.  I get an Error Message while relocating saying “You don’t have permission to access Lesser Sunda Islands”.  I have repaired permissions and repaired the Aperture Library but I still get this message.  The sets that have relocated without trouble don’t appear to be any different,  Why would this be?