Regarding ETS Powerprep plus 3 scoring algorithm

Hello,
I have taken the ETS powerprep plus-3 official practice test earlier today and scored a 142 in the verbal reasoning section and a 153 in the quantitative reasoning section. I have doubts regarding the scoring algorithm. According to Greg’s video, if anyone gets 7 or above number of questions correct in the first verbal section, he/she should face the medium difficulty section and eventually gets bonus.
But in my case I got 7 questions correct in the first verbal section which was of medium difficulty level (Average difficulty level was 3.0). I thought I would get the next verbal section also of medium difficulty. But unfortunately, the second verbal section’s difficulty level was averaging 1.5 which is obviously of easy difficulty level. I got correct 8 questions this time. But instead of getting bonus according to Greg, I got penalty of 3 points and ended up getting 142.
In the 1st quant section which was of medium difficulty (Average difficulty level 2.9), I got 11 questions correct. So, according to Greg, I should get medium difficulty in the 2nd quant section ( to some extent it might be termed as medium as the average difficulty level was 2.4) and should end up getting some bonus points. But in the 2nd quant section I got 15 questions correct. Therefore I thought I would get 130+11+15=156 but I ended up getting a pennalty again and got 153.
I am really confused about the ETS algorithm. Please help me out.