  COMMAND INSERTPOINT
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    Purpose: Insert a point into a face (like Imagine's "fracture")
             (default position: centered inside the face)
      Usage: INSERTPOINT(<objectID>,<faceID>[,<x>,<y>,<z>])
   Examples: insertpoint(1,133)
             insertpoint(1,12,-6.0,0.0,12.0)
      Notes: Subgroups and face-colors will be updated correctly
