Affiliates plugin does not count registrations

I am trynig to use the affiliate plugin, but for some reason I cannot get the count of registrations...
I am using the Profile Builder Pro (http://www.cozmoslabs.com/wordpress-profile-builder/) for registration and profile forms.
Where should I look at?
I see that the cookie is set correctly:
"Affiliate Debug : I have recorded a cookie from ..... . Any purchases will be assigned to that account for 30 days after the click."
Any help appreciated.