here's the first incarnation of Zebra VST for MacOS X:
http://www.u-he.com/ZebraVST.zip
It is no less than a VSTi that hosts the Audio Unit, so you need that installed.
But be warned: It's quite buggy. The graphics disappear, then come back when you close the window. No automation, nor settings saving with song. No sync to host tempo.
At least, you got an AU running in your preferred VST host
Cheers,
