Copy or save? And as user or admin?
We need some clarity: "can't copy complete files"? As you probably don't mean 1/2 files, do you mean folders? Can users save files from applications while logged in as user not as admin to a folder?
Try to create a new folder with access and can that be used by different users? If yes, as a user (not an admin), copy, (don't move) all content from old to new folder. Then that will work.
Just for interest, have you tried Calendar and address book successfully, I haven't yet.