After further investigation with this very issue I would call it a bug for sure..........but someone else should confirm it before I report it as such........
If you set up permissions on most anything for my site to, "JUST ME," it then becomes irreversible. IOW I can't change the permissions back to share with others. I noticed this quite a few times and ignored it but this is at issue. I just uploaded a file and when I set the permissions correct right from the start it worked perfectly. I had already set it up to just me before and I could not get it to reverse for the system. It is quite easy to choose a the privacy group but they too do not have access if I STARTED with just me..........Can someone test this on their site? If it does not come back as a bug how would I correct this? I noticed this to be VERY TRUE when I could not share anything with Facebook if I EVER started with, "Just ME."