If anyone wishes to try the development versions of OpenOCD, those can be found in Download > Software > OpenOCD dev

Currently there are two packages with the most recent version - one for 32-bit systems, the other for 64-bit versions. The package is a zip archive of complete OpenOCD tree (executable, dlls, cfgs, drivers, info, etc.).

The important part about 64-bit versions goes like this:

WARNING: THIS PACKAGE SHOULD BE CONSIDERED AS HIGHLY EXPERIMENTAL! The details
of 64-bit support are yet to be discovered. The packages in /drivers/
won't work on 64-bit system, but they are a good starting point. Visit
OpenOCD's mailing list for help and support. Make sure to post some
feedback there to help me develop a working solution for 64-bit systems.

IMHO the most comprehensive places about 64-bit Windows vs. OpenOCD are these topics on sparkfun forum: #1, #2. Make sure to read those two before starting to test the 64-bit package.

I plan on posting such packages regularly (especially in the RC phase)

Anyway - please test them and post your feedback on the OpenOCD mailing list.