Blender is not the problem. The material file is. Look at C:\Users\{your_name}\Outerra\packages\{your_ot_name}\{object_name}\{object_name}.mtl
Change the f0 value to control the shinyness. Its a value between 0.0 and 1.0. Try some values out. Start with f0 = 0.02 and increase the value to the point of satisfaction. You also can toy around with the roughness parameter.