Cant the permissions be edited if you pick from the filemenu "Details" (by pressing the file for a while, where you can pick also Clip, Open with, delete...), and modify the tickboxes of "rwx" from there and click save? Or do you mean something other than that? This at least worked for some of my files. I myself can edit the permission in for example /user folder, but cant do that in /user/MyDocs, maybe because of different filesystems or something?