LR 10.3 + NIkon D610 + Tethered LiveView worked ONCE, now won't at all.

I got all excited when LR announced LiveView support for D610 tethering on Win10.

I upgraded to 10.3, hooked up my camerastarted tethering and clicked LIveView.

I heard the mirror flip up and . . . W O W ! ! . . . LiveView!

I was in love! Totally fantastic, big help to my studio work, broke out the champagne!

Then, I went to the studio the next day and . . . NO GO!

Suddenly felt hungover.

LiveView only shows a grey window. No mirror-up sound. 

Camera fires from the tethered shutter release, images come into the computer, etc. But no LiveView (and AF seems broken as well).

I tried this cable, that cable, rebooting the computer, R&R battery in camera, delete LR prefs, etc. All the recos from HERE but, no joy.

I REALLY REALLY REALLY want LiveView to work!

You see, I work with lots of dogs and down-low shots are super-impotrant to me (I even designed and built a custom camera stand so my camrea can be lowered right to ground level) BUT I have a funky knee that seriously does NOT like kneeling on it, so live view is GREATLY DESIRED.

Any thoughts? 

Oddly enough, LiveView will not work on my main computer either! Maybe Adobe trashed something in my camera? 

So: LiveView worked ONCE, now it won't at all. 

: - (

Bummer.

Next up: uninstall LR and re-install it.