Adding Columns to the Gallery Widget

[Initiostar]

What's the secret to adding Portrait Pages to the Gallery that's set up for Landscape? I changed to Image size for the placeholder, but when I insert Portrait images, they are still Landscape

No secret, open the widget, select any one page, File, Page Options, change to portrait, or change the width and height to custom dimensions. Use the Page & Layer Gallery to duplicate and reorder as required. This particular widget seems to sort itself out and reorder the layout (not guaranteed though!)