I just upgraded to the latest build of Crackling CyanogenOS via the zip available directly from cyngyn.
I just flashed it in TWRP 3.0.2, along with Xposed, Titanium, and SuperSU.
Rebooted and all data was still there so there is no /data wipe in the script.
In my list of zips to flash I also re-flashed TWRP 3.0.2 at the end in order to maintain TWRP as the recovery. I did not test it without so I do not know if the recovery is normally overwritten.
The first boot took about 20 minutes.
Nonetheless, do a NANDroid at least and, if you're like me, you do a Titanium app backup, too.
Good luck!