Thanks Jason, that has nearly fixed it.
The only thing I cannot fix, is the width of the ribbon, which seems to be set in js for the fullsize+ribbon+lightbox
I have edited the css class, and previewed the ribbon width through firebug, but the width stubbornly refuses to change permanently
I have edited the gallery.js to change the number of thumbnails displayed, which helps, but the width doesn't match the div above