Edit: I'm on a Mac Mini late 2012, i7 quad running OSX 10.9.5
I've downloaded the demo, installed it and fired up Cubase.
No Sound... I fired up Biotek and other VSTi synths, they are working fine.
The same result in Logic Pro X.
I'm sure it can and will be fixed asap.
(Never mind the disappointment after waiting for days for WR to launch.)
BTW, does anyone who's purchased the full version have the same issue?