I dont use Windows, but a few Windows buddies have told me that they get ASIO to work with the Lampi USB passing DSD. Jabs is one, for example.
DSD256 is solved, but will take a couple months to design and print the PCBs for wide scale availability. I hear the new design improves all DSD playback rates!
I'd be interested in hearing how they were able to get ASIO support working with the Lampizator DSD DAC. I checked with Lampizator when reviewing the DAC and they told me DoP was the only supported option for playback.
On DSD 256, I hear it's under development. I'm ready to send in my DAC for the upgrade when the time comes !