The Universal build contains 32-bit and 64-bit code, so it shouldn't work any differently.
Did you say that everything worked fine in Mixxx 1.9.2? (You can download it again from here
Let's isolate the issues you're seeing in 1.10.0: (close Mixxx before turning off/on any of the devices.)
1) With only the SCS.1m (mixer) on, does it work correctly by itself?
2) With only the SCS.1d (deck) on, does the platter stop moving when Mixxx initializes it and it lights up?
3) Does the platter stop if you switch from Vinyl to Control or Browse mode? (It should.)
4) Does the platter stop if you press Deck Select?
5) Does the platter stop if you press Play or Cue a couple of times? (with no song loaded)
6) What firmware version is on your mixer and deck? Press Setup and it will show it on the LCD displays. The deck requires firmware 1.25 or later. (1.27 is the latest.)
Mixxx Developer - Controller Specialist
Mixxx Windows package maintainer