made an animation that rotates the character by rotating its root bone and I want to use it with a root motion system. But, I don’t think that “Root motion Rotation” is working. Inside my AnimMontage, when I check the “Enable Root Motion Rotation” checkbox, the character stops rotating on the preview animation.
That is expected behavior. We do not actually simulate root motion in the preview, so what you see is the animation stripped of the root motion. So the character standing in place if what you’d expect. We will have root motion simulation in editor at some point, this is something we want to add.
If you play this in-game on a character that has physics enabled, you will see him rotate.
Well, but I am not seeing the rotation in game also. 
Let me ask this so that I am sure of how this is suppost to work.
I have an animation that has the root moving and rotating. So, after calling my animMontage( that has all the root motion enabled ) do I still need to move my character, by using “Set Location” or “Move Component to”, ou the character will be driven by the root animation?
This root motion is a pain in the a** to work with. Rotation is for sure not working. Translation is working only if I use flying state, but at least works.
So, you could improve this a little bit. 
Well, root motion translation also is buggy. Sometimes it works, sometimes it doesn’t.
Look here on this video:
I just added a Print string to my blueprint, and Root Motion stopped working. How can we work with that? I remove the print string, compile and save, and now root motion is working again.
Well, I made another test. Root motion was working. So, I save everything and close the editor. Then I openned it again, and played the level… Surprise, root motion is not working again.