This is the basic Newton SDK FAQ... most of these topics were taken from the official Newton SDK forums.
Q: Is there a MAC / LINUX version of Newton?
Q: What languages are supported, where do I get headers?
Q: Can I manually dynamically move an otherwise static TriMesh without having objects sink through it?
Q: How can I control an object using a physics engine?
Q: The collision tree does not seem to work correctly?
Q: What's the difference between AddForce and SetForce?
Q: Why isn't raycast working sometimes?
Q: How do I remove drag from the system completely?
Q: Blowing up in extremes
Q: My newton bodies aren't updating and my callbacks are set up correctly!
Q: Linker errors
Q: What is "Time-slicing"?
Q: What value should I pass to "NewtonUpdate?