Urm.
'Growler' I hope your not thinking zbrush is a plugin for gmax/3dsm. The only way zbrush would work with max/gmax is either creating normal maps for your low polygon models, or taking your high polygon model into max, and playing around with it in there, (gmax cannot create normal maps) There is external programs that can create normal maps though.
Z Brush is best for making high polygon models out of pre made models, (It isnt very good at creating a model straight from z brush, z brush is also used to make 2.5 axis paintings, (I cant really explain it straight, if your really into zbrush, go to their homepage and download some tuturials from their site, they have a nifty little demo of zbrush, (you can use everything in it, just you cannot export your models, or import your models from another 3d program) The demo is only around 16mb as I remember, go have a try at it.
Zbrush demo:
http://pixologic.com/order/demoselect.html
(It also has some tutorials on that page if you click Zbrush classroom)
Its looking good tek, im glad your learning zbrush