question about prima rake(back)

[Grandezza]

Ok so I just got a Prima account set up w/ 60% rakeback. I get 30% from the site and 30% from the affiliate right?

Played a session today raked $20. I check my rakeback status on the site. It says I raked $8.5 and I will recieve $2.5 in rakeback. Why is this number not the same as the one in my PT. On other sites I could just multiply my rake in PT with my rakeback percentage and I had my rakeback. What will I recieve from my affiliate? $2.5?

Does this has anything to do w/ contributed or deal? MGR? Sorry if I could've found the answer to all of this in the FAQ but read through and didn't really get it.