The Physics solver Properties pane lets you specify basic constraints or default conventions that govern the solving behavior.
Note On 64-bit systems, the Physics solver cannot process objects that have degenerated polygons or invalid normals. When this
occurs, a warning message appears that identifies the models that have this problematic geometry, and bounding boxes are used
to approximate these shapes instead. Using these bounding boxes for the joint solve may produce solve results that differ
from the expected behavior. If possible, use the Cube, Capsule, or Sphere approximations to match your geometry with more
precision. For more complex geometry, reconstruct your model with 3D software to avoid these non-standard geometry problems.
This problem does not occur in the 32-bit version of MotionBuilder.