Yeah, go with higher resistance wire... even 30 might be good. Wire is pretty inexpensive, you might want to have 28, 30 and 32 on hand. On an RBA, coils tend to be 3 to 5 wraps... with 28, that's the sub-ohm/low 1's... 30 will be in the middle 1's and with 32, you'll be up around 2 ohms.
Even with 6 wraps, you might not hit the floor of the ZMax... You are really close to 1.5 ohms at that point (just guessing based on the wire and size of the wick).
Now, I don't know much about the ZMax, but what does it say with nothing attached? Just asking since the RSST has an adjustable center post... if not adjusted right, it won't be making contact with the center post on the ZMax. But it all depends on what it says... I know my Vamo will read resistances at least down to 0.7 ohms (even though it won't fire down there), and with nothing attached, I get 9.9 ohms.