Finally found a Mac-friendly DLNA that (kinda) works with my MacBook and the BD390-- Twonky!
http://www.twonkyvision.de/
30-day free trial, & buy for $29.95 if you like it.
Easy to install, as has been everything else with the BD390.
The user interface for it on the BD390 is fairly ho-hum. The connectivity to my wifi is excellent, no drop outs so far. Since our friend the BD390 (quite ridiculously) won't play mp4's, I converted a few to mp3 with iTunes to test it out, and the sound is excellent (zero loss in quality). For further annoyance, it still finds all the mp4 files on my drive too, so I have to wade thru 2 copies of each file when sorting the lists out between mp3 & mp4... Found all my photos nicely though, and as a nice touch you can still be playing your music files while running your slideshows. Haven't fully tried out playing video files, though I see already it won't play my iMovie clips. Will let ya know if it's a raging success (don't hold your breath).
I guess I'm not entirely clear on what issues I can blame on the BD390's "My Media" menus and what I can blame on Twonky, but with a name like Twonky, I mean, come on...

Overall, it delivers about as much as you'd expect from a rinky dink little German DLNA named Twonky. With a little more tinkering on my part, it might not be half bad. And really, I shouldn't be too hard on it, as it's the only one I've found so far that works at all, so hooray! One (small) step closer to home theater nirvana.

(Did I mention I love saying Twonky?)