If it is true that we are in True Reality when we are following God’s will, is it also true that because of less good actions we move in and out of True Reality? In other words, do we sometimes temporarily access True Reality?

Yes, that happens because the Earth plane is a school and you are in the process of always learning. Your constant trajectory should always be to be in True Reality. Being in a positive flow one day, but being some way negative another day is not a free pass or allowance because you will always need to account for the negatives that you create. Therefore always strive to be in alignment with all that is around you. One way to attain True Reality is to fully embrace that you are part of a unified field. Being in a human body can make that a real challenge, but you can experience being part of Oneness more easily if you start seeing yourself as a body of molecular or energy makeup. In that state you are capable of seeing things more fluidly. Then you can more easily see that you are Spirit.