Hey Tony,
Great Job Tony truely awesome work. I don't have a Mac so I was not going to be any help on that one. I am not having the same problems as you for ZBrush 3.5 on Linux Ubuntu 9.04 except for the not accessing all of my ram part. I wonder if your other problems with ZB 3.5 on the Mac has to do with the configuration of wine. ZBrush 3.5 seems to only be accessing around at max 3.0 GB when I have 12 GB in my system. I was also running a system monitor on it, and it was not really taxing my 8 cores all that much.
Most of the time they were sitting at around 30%. I will have to see if I get the same problem in Windows. I wonder if this has anything to do with the fact that its 32 bit program. I know 32 bit is suppose to max at 3.0 GB of ram due to lack of bits to calculate the higher numbers for the larger amounts of ram. I am curious, does your ZB 3.5 max out at 3.0 GB on your Mac wine?
Cheers,
Nate Nesler