// Ok, now we have a thickness and a bulk material of the correct name,
// we can make our own surface material.
- Material.Surface surface = new Material.Surface( convertedMaterialName, bulk.getDensity() * thickness , true);
+ Material.Surface surface = (Material.Surface) Material.newUserMaterial(Material.Type.SURFACE, convertedMaterialName, bulk.getDensity() * thickness);
this.put(surface);