This serie of measurements concern the analysis of the object once transformed to a triangular Mesh (see 3DViewer Visualisation). The surface computed in mesh mode could be a accurate measure of the actual surface of the object. You can also think of smoothing a bit the surface before computing the area. The 3D convex Hull (next release) performs a outside convex hull of the object, and then comparing the volume of the object and the volume of the corresponding convex hull, you get an idea of invaginations inside the object.