When I upload the files, they are immediately uploaded into the site/assets/uploads/ folder rather than the site/assets/image-gallery/{page name}/Default-Album/ folder. This is before I save the page or open Files&Images. I check by looking in the folder on the server directly.
That never seems to change, just where the page is referencing the files. It seems the CMS view is referencing cropped/resized versions in the site/assets/_resized/ folder, but when I leave and come back it either can't find them, or they have been removed.
If I create a new album, let's say 'bob', and upload there, then the files end up in site/assets/image-gallery/{page-name}/Bob/ with a _resized folder in there for the thumbnails.
So when just using Default it doesn't upload to the correct place at all, and it seems weird that the preview would work. After going to Files & Images it seems to set the ImageGalleryPage right so that it can't see the files since they are in the wrong place.