Hi Bruce,
Hopefully you figured it out by now... I just did after stumbling around for a bit, because one cannot change the sequence number from choosing a photo to edit (photos-edit). Instead..
Go to an album and view a page of thumbnail images (usually about 12 thumbnails per page).
Click on the "Edit these photos" link. This bulk view of photos-edit shows the sequence (order_n) referred to above.
cheers,
Torben
