Documentation for zwave.switchMultilevelV2 (and zwave in general)?

I went to take a stab at my first device type, adding support for Cooper’s RF9540’s ramp rate. Cribbing from “Dimmer Switch”, parts of some implementation are there, though incomplete (no capabilities or attributes tied to it) but the documentation for zwave.switchMultilevelV2 doesn’t give any hints as to what the underlying implementation is doing.

Is there somewhere else I should be looking?

I don’t know anything about it myself, but did you see the example here? It looks like it has a dimmer implmentation using switchMultilevelV2: