Hmm, I've played with the file a little bit. Don't know how to make it work. From the results of tightpage, it looks like the graphic is being produced and the size is calculated, but is not actually placed in the document. It's probably some kind of driver incompatibility between tikz and preview, but I'm not sure how to tackle it.
Sorry I can't give you more help than that. -Andy -------------------------------------------------- Subscriptions, Archive, and List information, etc.: http://tug.org/mailman/listinfo/xetex