Same problem I have, Kev. Most of my web imagery, is of the bunkers post-war, and many modifications have been made to those bunkers over the years. The few books that I do have on the wartime bunkers, are filled with soft and grainy images, though I have been able to piece together enough data to scratch build a bunker that is, at worst, an amalgamation of miscellaneous elements from all of the various bunkers. Apparently, no two bunker complexes used the exact same architecture, which is perfectly understandable, but it makes piecing together an overall image of a specific bunker, very difficult, if not impossible.
Attaching images is as easy as clicking on the "choose files" link, navigating to the specific folder where your image resides, then double-clicking it. This is as far as I've progressed to date, but I'd like to finish it this winter, to take to Omaha in 2017. We'll see how that goes.