It's basically the same version as 30.7 (for orbiter BETA) - as could be downloaded
here .
The version information (Windows File Version info via right click on D3D9Client.dll) will show that, too.
Nothing mayor. Mainly it was "tweaked" to be included in the OpenOrbiter build-chain and to be build as 64-bit version!
No, sorry. The "what's new" page is not (yet) planned

Most of the changes are discussesd and addressed in this forum thread.
I know that that is not a good solution.
Yes, yes it does!
The latest 64-bit build atrifact contains the 64-bit versions of OpenOrbiter & D3D9Client.