I've revised the format of the site and the Box widget for downloads has disappeared, likely for good. In fact, this is the reason it disappeared awhile ago; it doesn't quite fit the way I want to manage downloads here or the desired layout.
For the time being, I'll just provide url's for dl's in the context of each article. As some of you may have noticed, older urls are broken in some cases, but if you peruse the dl's folder most items should be there. Here's the link for the files from the Box widget, in aggregate... http://www.box.com/s/oj8zyld11237imsm8f81