I used to drive an auto (not a Zed), and in my country winters can be quite snowy.
The tricky thing was to avoid accidental kickdown or, for that matter, any abrupt gear changes that could unsettle the car (an equivalent of downshifting and quickly releasing the clutch in a manual car). In general, any sudden input, like braking or swerving, is not advisable.
I would go for the first option, namely: go into the manual mode and choose a lower, long gear (3 or 2) before the descent. Gently drive down the hill, braking with the engine only (i.e. gently lifting your foot off the accelerator).
For me, winter driving is lazy driving - minimum driver input, slow, lazy moves, gentleness. You'll like it!
Do not roll in the neutral, as it is destructive for the automatic hydrokinetic transmission.