WD Live streams fine WITHOUT MC. What I do is simply plug it into a tv or monitor, switch to the correct input source and bam, you're done. IF there's an advantage to combining MC and WD to work as a "renderer", I haven't found it and no post I've read explains any advantage either. If such a post exists, somebody enlighten me.
In fact I find MC "dumb" in some regards with respect to playing back files in that you need to add files to the database FIRST, which for some purposes is fine, but a pain in the butt for others. WD simply scans whatever file source you have it can play and shows still images, video and music files and just plays them. No muss, no fuss. Isn't that what most REALLY want?
As far as DLNA (Digital Living Network Alliance) that is just another poorly thought out sometimes even worse implemented scheme that may or may not work as excepted, just like firewire, USB, and any number of other so-called "standards" have their flaws and pitfalls. Read that to mean DLNA works to verying degrees depending on the devices claiming to support it. You best bet getting DLNA to work is look for "DLNA Certified" on both player (ie WD Live) and the device (televison/monitor you expect to play files on.