Hi Irene,Have you downloaded the Mac downloader? You will need this installed to be able to download content. In case you need it the link is below.
http://file.reallusion.com/CTA2_downloader_mac.dmg
Also do ensure you have your copy of CrazyTalk Animator 2 updated to the latest version which 2.15. You can check this in CTA2 by going to Help > Check For Update.