4
You've done everything correct, except when you batch add your files, the folders you actually uploaded to '/what/ever/folder' needs to be chmod 777 as well.
Just to let you know, it will only add 15 images at a time. Just go back to batch add, and the images that havn't been added to the DB yet will be checked, while the images that are added will not be checked. I discovered this when adding some 50 pictures one day.
Good luck!