I have the toolset running in wine on Ubuntu. When i did NWN stuff on my mac laptop i dual booted. If you partition the Windows side as FAT32 or NTFS (and purchase a special NTFS driver for the Mac) you can store all of the NWN data on the windows partition but still access it fully when booted in OS X. I used aliases so that the mac installation pulled the data directly from the windows partition.
I'm much happier running this using Wine on Ubuntu though where I also use the alias trick to keep my NWN data all in the same location (unduplicated).