This isn’t the best gallery in the world, but it depicts how you can visualize individual pages of an InDesign project after they have been converted to JPGs and uploaded as a slideshow.
I would create a slideshow that offer larger initial images and open to full screen or a much larger light box for the purpose of your contest book, or whatever the title is of that InDesign project being mentioned in that thread on our Trello cards.
To convert from InDesign:
save as pdf
convert individual pages to jpgs – resize as necessary
upload individually into slideshow gallery
embed gallery in a page
much faster access for people accessing the images, much less data for those doing so on handhelds.