Newton is sorely lacking in some very necessary features to make this work. Newton doesn't have a character controller, and it doesn't allow you to create one because you can't just position a physics body somewhere, like you can with a DP kinematic object.
I use Dark AI+Dark Physics in Geisha House, and I did as well in my Dark Physics compo. They work nicely together, if you code it right.
1. Using Character Controllers:
Character controllers aren't positioned, they're pushed. When using Dark AI, you want the controller to go where the AI says it is. So, you update your AI first. You point the character controller in that direction, push it the entire distance between the two points, then rotate it back to the AI Y-angle, as reported by Dark AI.
You
supposed to, at this point, manually position the AI body to the new position of the controller since the real position might be different than the place that it was supposed to go. The same thing applies not just to Physics, but to collision as well. However,
this does not work! Each and every time you reposition the AI manually, Dark AI reports that the entity is moving, even though it's really not. So, your character will never do anything except for animate walking, based on Dark AI feedback. I reported this as a bug and it was confirmed, but nothing has been done about it.
Easy to work around. I only manually update the AI position if the AI position and the real position are more than the height of the model apart. Mine are 60 units tall, so if they are more than 60 units apart, I update the AI pos to the real one. Simple and it works. By the way, use 2D distance checks.
2. DP without a character controller:
Admittedly, Dark Physics has a few issues. As a rigid body simulator, it can't be beaten. All of the extra things seem to be a bit broken. Particles stink, collision feedback is lame, cloth isn't usable, and character controllers aren't really any good. However, since DP rocks as a rigid body simulator, it's easy to set up your own character controller system.
I use two boxes, a controlBox and a pushBox. The controlBox is a regular primitive box, the size of the character. It is not a physics body, it is set up with Sparky's collision. I can position it wherever I like without any problems, and my gravity works perfectly on it. I use Sparky's sphere-casting to provide sliding collision so that it won't run into anything that it shouldn't, especially buildings and characters.
Inside of that box I place a smaller box, offset from the ground and smaller than both the controlBox and the sphere-casting radius. This box is there to push aside rigid bodies that you're walking over. Anything big you'll slide around, anything small you'll push aside. Flying debris will also bounce nicely off of you. Works great. I use DP commands to manually position the pushBox at the controlBox's location each loop.
I use the same Dark AI method that I described above. It actually has nothing to do with the physics, and everything to do with the collision.
3. Newton
Sorry, I tried REALLY hard to make this work. The good folks on Newton Wrapper Hill had no advice for me to make the character controller work. I was using a rigid box with an upright joint. I could apply forward force to make it move forward. The problem was rotational force. I couldn't make the damned thing act right, no matter how much friction or how little rotational force I added it would start spinning like a top. Then when I pushed it forward it would act retarded. Maybe you'll be able to figure it out, but it sure didn't work for me. If you do get it to work then you'd use the same method that I use for the character controller.
Good luck.
Come see the WIP!