I've googled, and not found a solution (perhaps I simply missed it). At home, in my office, I've assigned keyboard shortcuts—or actually, it may just be the default setting, the page down and page up keys—for 'go to next spread' and 'go to previous spread'. But I'm travelling, and nothing I do with my MacBook Pro and the external keyboard I carry with me works. I should say right now that I like to look at my project with two pages side-by-side... on a MBP screen, that means I'm at approx 56%. Anyway, if I hit the page down key, I go down all right, but also over to the left, to feature (I guess) the next page, and not the next spread. This means that every time I want to go down, to see the next spread, I hit this page down key and then have to scroll, to bring both pages in front of me.