Hi James, for the display check out here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=7777.1620

That 'arrow3d' factory will make an annotation leader object with the property set on it for rotating the arrowhead plane so it's always facing the viewer. Should be good for a vector direction display.

re:
> Another useful feature would be the inclusion of the facility to unify normals across a polysurface.

This should happen automatically - when surfaces are joined together they should evaluate normals on a consistent side which will be to the exterior if it's a solid.

- Michael