As it stands, you can't save double pages as a single image if you're on the double page mode. So it'd be impossible to save double-spreads in comics/mangas that don't have their double-spreads merged as a single page.
I think what the save function should do is to save what you're currently viewing as a standalone image, rather than saving each viewed-page individually. If one wants separate images, they simply can switch to single-page mode and save each page once.
YACReader
