Hey,
Just installed the core of Cakewalk Platinum on a 10122 build of Windows 10 Preview (64-bit), and a very cursory test shows it seems to work well !
As expected, the Windows 8 driver for my Roland Quad Capture didn't work and I'll have to wait for an official release of Roland, hopefully soon after the launch of Windows 10.
What surprised me very much: by choosing compatibility option with Windows 7, I could install the Tascam FW-1884 1.80 drivers, without any FireWire Legacy tricks, and it works ! (same, very cursory test, playing of a project in Sonar + listening music with Groove (aka Xbox music) when configured as default sound peripheral).