Hi Esther -
I have Crazy Talk 8 as well as iClone 6 & 7 with the R.H.H. pack. The Realistic Human Head package integrates into the 'Avatar' - 'Heads' section of your project manager in iClone, Crazy Talk 8, AND Character Creators 1 & 2.
If you don't see them there, There are 2 ways to get them into your Project manager I can think of. Go to your client area in your Reallusion account. There you will see your purchases. Download the install manager version, and when you click on the file it sends, their server will re-install it for you. If it puts up a window that says it is already installed, select the "OVERWRITE" option. After that, it should be available in Crazy Talk 8, as well as iClone 6 & 7 in the 'Avatar' 'Heads" location on the template side.
If this does NOT work, I can only offer the Windows solution. I do not know how this applies to Mac. You can still access them through the following windows explorer location(s) and apply them directly from THERE by selecting your character, in and dragging & dropping the desired head file to your character directly from the Windows Explorer window. I hate doing it that way, but I've had this problem more than once, seems to be endemic to Reallusion. Open your Windows Explorer & paste this location to find the folder you'll need: C:\Users\Public\Documents\Reallusion\Shared Templates\RL Head.
I hope this helps! Good luck, ~Val~
Val RogueAnanda