Basically, a dmr plugin is nothing else but an extension to the iptv plugin. I don't know if the iptv plugin is able to stream http streams. If it does, the dmr plugin is more or less ready to use. However, the main part of the plugin is the controller which implements browse or search. So, if there's someone out there, I would really suggest to separate the renderer from the controller as it is easier to manage them.
The server does the same: it implements the required UPnP stuff for browsing and searching, but all the streaming part shall be handled by another plugin like streamdev.
So, the question is: is there any plugin which is able to receive HTTP streams for any arbitrary content like images or videos?