Since there have been very visits to this post, I will assume that there are very few people using Vue, C4d and the Mac and for that reason the following will most likely go unnoticed by the user community, nevertheless, I feel obligated to say the following about said software/hardware combination:

I have been testing the PLE edition of Vue 7.5 xstream for the Mac (8core, 3.2ghz, 4gig ram, 3tb raid) and C4d and have met with nothing less than persistent frustration.  Vue has been responsible for a myriad of crashes under a variety of circumstances but most frequently when working with materials, either assigning or editing same or when rendering either small distributions, not large, of ecosystems or even simple scenes.  In addition, there have been hangups that occasionally and miraculously seem to self-resolve while others do not.  In all, I would have to say that, at least from my experience and in my opinion, the aforementioned hardware/software combination, regardless of its tremendous potential, is currently not workable for my purposes and I have removed it from my computer.