I was able to get the missing write permissions onto the folder Data and all of it children. I attempt to upload an image and received the same earlier error message. Now I don't even get the Image Gallery page.
I noticed that on my localhost and my host that under GalleryImages a folder "9" is created with the 3 subfolders that you reference below. In other words, an extra layer. Could this be the source of my problems. The creator adds the layer "9", but the consumer doesn't know about it?