Document Exchange was designed to be a flexible framework with which you could do all necessary tasks of document management, but also on which you could build other applications that go beyond the regular. The idea of extending the module came from being involved in custom projects back in the days of the first version. It quickly became apparent that all customers would be on forks of the module and just keeping track of this was a challenge as best.
One area in which we often get questions for adaptation is the UI. Obviously there is no 'one-size-fits-all' in this market. The current version offers 2 UIs out of the box: one elaborate UI with many Ajax features, and one simplified version that does not offer any Ajax features. Over the years other UI versions have been developed for customers. These extensions were nearly always 'read-only'. In other words, they offered a new way of viewing content of the document exchange, without the ability to add or edit content. These modules have now been made available for download on a new extensions page:
http://www.bring2mind.net/DocumentExchange/Extensions/tabid/180/Default.aspx
Most of these modules have been 'floating around' on this site and I've sent them on demand, but now they're ordered in a simple list. For customers of DMX the source code is also available. The page itself uses one of the addons (Flexlist) to offer download links to the extensions.
My intention is to add other types of extensions in the near future as well, including non-free extensions. For now all that is on that page is freely downloadable.
Have fun with your document management system and let me know if you need anything ...