If you read the UPNP/DLNA thread, you'll notice that it's no longer being developed. And that it works as is for some people and not for others. For those that it isn't working, it becomes a memory hog. To the point of blue-screening the PC. Even if it isn't being used. Just having the plugin installed can cause the issue.
Steven has abandoned it because he just doesn't have the time to work on a plugin where the destination source has so many variables. He's offered up the source code to anyone who wants to take it over, but no one has stepped up.
That being said, I doubt very much he would put any time into your request. I do not speak for Steven, but if my memory is correct, he did the WiFi Android app as an experiment to see if he could. Also, I'm not sure Steven -wants- to hit the jackpot. He is the only source of official support. He created and maintains MB as a hobby. Hitting the jackpot would increase the number of questions and issues and could quite possibly become overwhelming. Again, these are just my thoughts, not Steven's.
Since the forum is the only method of support, other more experienced users provide answers and suggestions and troubleshooting tips so that Steven doesn't have to. When a major developer (Google?) announced they were stopping their music service, the number of new members here increased dramatically. With many, many questions and complaints.
Just my two cents.