Ok, give this a shot...
The rotaries remain CC with most being set to absolute with a value of 0-127.
I tried the gain controls at relative but they were quite unresponsive, but it's something that I may need to address in the template for the S4. As for now, they're set to absolute but don't have stops on the gain controls so they may need addressed.
All the buttons and knobs with push buttons are set to MIDI Notes as gates. Meaning you get a 127 when you press them, and a 00 when you lift. The same goes for the tops of the jog wheels.
Most everything else is a CC message as well with a range of 0 to 127.
Keep in mind the shift and deck c/d buttons are NOT modifiers. They actually change the pages in hardware and send on different MIDI channels. That means when Cross gets 4 decks the functionality is already there without having to add modifiers or get creative.
All in all, the S4 is a pretty nice bit of kit with a lot of flexibility if you're willing to put in the time. Sure they use a proprietary protocol for Traktor, but at least they put in the MIDI functionality so we can hack it and map it.

If you need anything tweaked let me know... I'm eager to give this a shot.

I have a big event this weekend and likely won't be working on the mapping much between now and then, but afterwards, I'd love to dig in some more and do some testing.