Second, I will share my experince that I had last night. I OC 2.0 my wife's car over a month ago. After washing it last night, I too noted a lack of beading on the hood and roof but the rest of the car was fine.
I decided to rewash it. This time, however, I added Optimum Power Clean to the Optimum Car Soap. I added a half an ounceof OPC and 1 1/2 OCS to the foam gun. With my wash bucket I added 2 ounces of OPC to OCS to 2 3/4 of water.
After the rewash, the beading/sheeting wash back.
This past week was BAD with the Spring contaminants and spotty rain. The layer was really thick. It was so thick that even my wife, who normally doesn't say anything, told me her car was " philthy."
Hopefully it's a quick fix for you.