Quick question - where/how do I get this shader to work? It's installed, I can see it in the Finder... but I can't find it anywhere when I'm in A:M itself.

In the hair material go to:

material/hair emitter/surface/diffuse render shader/muhhair

material/hair emitter/surface/specular render shader./muhhair

Good luck in figuring out what the settings should be. Start with the defaults and experiment from there

And when you go to render make sure you have rendering options/plugin shaders/ON

Huh, weird! I swear those weren't there before. Thanks!!

One other thing, I remember someone mentioning tapering the start and end of the hairs, with the middle being thicker. Where do I find that option?

In the hair material (NOT in the instance in the model) select hair emitter/thickness and have the timeline open and set to graph mode

zoom in the timeline so that you can see at least 0-100% on x axis. In the timeline go to the percentage and type in thickness - shape the curve (hair emitter shape) however you want. I've made an hourglass type shape - thin at the ends and in the middle.

Excellent, thanks.