Microsoft got back to me, it was indeed the 'reputation' of the binary. It has now established the necessary reputation and when updating the SmartScreen definitions and re-downloading the binary, the warning doesn't appear anymore.
Oh no! That is disappointing! I've been trying to use the Seaboard with Elektron gear (putting the same patch on all four tracks) and being able to easily see the messages I am sending would be very helpful. I think about updating in the next few days. Thanks for getting back to me on this!!
