The pack you have purchased is a CrazyTalk Animator 1 pack which includes G1 (Generation 1) character types.
Unfortunately, you need to apply a G1 head to these characters to replace the blank grey place holder head. You can't apply G2, G3 or G3 360 heads to G1 characters.
Please try downloading the G1 Bonus pack from your Reallusion Account Registration page. Just click the Download link for Cartoon Animator 4 to find it. This includes some G1 heads that you can apply to these characters.https://www.reallusion.com/member/#/en/registration