I got Here Navigator on the S2 to work. First, I downloaded Here Navigator on the S2 from the Gear Store on the device, and also downloaded Here Maps from the Play Store> Also, you have to register for a free account in the Here Maps app if you want to download offline maps. I did that and then downloaded the map for my state.
Fortunately, the downloads were fast while on wifi, and, while still on wifi, I spoke my desired destination into the S2 and it understood perfectly.
After a couple of seconds, while having the S2 paired to my Note 4, I heard the spoken directions on the phone, while the S2 showed the distance to the next turn, accurately, so far.
Also, since I'm using a S2 Sport (ie,not the GPS-enabled 3G model), you have to keep GPS active on your phone while you're navigating.