You can convert them just look in the Tip's n Tricks forum.
If you have the Windows Audiophile version you can use that on the Mac as it will use the wav files.
You just need to rename the Library folders to LibraryM,
you have one in the RealTracks folder and one in the Direct Input folder.
If you want to use the Audiophile hard drive on both Win and Mac create a Windows folder symbolic link "Library" that points to the "LibraryM" folder, do the same for both Library folders then Windows BB will still find the Holds.