I am much less into zBrush animation as I wanted, but one thing you can animate for sure are the changes of layers in the tool palette.
http://docs.pixologic.com/user-guide/movies/timeline/
But watch out, a rotation won’t be a rotation but a layers morph.
I would love to know more about that either.
I found this by Steve Warner:
https://www.youtube.com/watch?v=p6H_fdSkVu0
This is the belonging thread at ZBC:
http://www.zbrushcentral.com/showthread.php?91827-Z4-Beta-Testing-By-Steve-Warner
Me, I tried to use the “import MDD” function in the layer menu.
Created a simple animation in softimage - exported the object OBJ and the animation as a mdd (point cache) file.
Loaded this into the layers and it worked. …Somehow, had to fiddle around and add a Key for layers in the time line.
As I saw, this should also be possible with blender. If that is a solution for you, you have to find out by yourself.
Me, I would really love to see more animation functions in zBrush like in the once started zAnimator script.
Good luckl