Wow... Bit by bit the evidence is telling a story.
IMO, I think that KC killed Caylee (I believe in the car), hid her body in the trunk of the car for nearly 3 days (if decomp in air was 2.6 days, let's say gases began a few hours). When she noticed the odor, knew she had to do something but didn't want body found. She drove to the house, backed the car in the garage, bagged lil Caylee and then drove over and disposed of her. I guess its possible the plastic bag came undone by animals who picked up the scent of decomp???