I just did my 19th MCO.
Contracting my pelvic floor muscles at the outbreath has become almost automatic so that gives me room to change other details of the meditation.
In previously sessions I would breathe in the energy into the energyball from outside my body directly to where the ball is at that moment.
What I learned from the book of Yang Jwing-Ming is that it is better to let the energy enter through the 3rd eye to the center of my brain and let it follow the path to the energyball along the points as depicted here:

It makes the meditation more complex again and will take a few sessions to get used to.
The last few sessions there is a sense of subtle heat around my sacral chakra and lower Dantian. Also there is strong pressure around my 3rd eye but that is standard for me when I do any meditation.
I don’t feel energy movement yet except when the ball moves from the crown to the 3rd eye , there the ball gets ‘sticky’ and it is difficult to move it to the throat.