Hi! Trying to answer from my experience - the CN was the hardest for us as well, but it seemed as if our baby-girl NEEDS it.
1. Supposed to drop the CN around 6 months, i waited for her to refuse it for several days in a row and then stopped offering it and it was dropped.
2. It was the hardest for me as well, but i insisted until several days in a row (i think over a week)
3. I would try as long as it's CN time - then i would exit the room - then re-enter it saying something like "i know you didn't sleep well, let's go to eat/play etc", just to emphasize that i did not give up because she's crying (so she won't start from the crying next time) but i gave up because it is time. This really helped.