Global Mapper v25.0

I am trying to load a new datum into GM How to load the file???

planes54
planes54 Global Mapper User
 I have a .prj file but it  gives me a error message that some data may be missing and fails to load have also tried using the EPSG code 2105  again a message 
Invalid EPSG Projection code
I have attached the .prj file that I have been trying to load
PROJCS["NZGD2000 / Mount Eden 2000",
    GEOGCS["NZGD2000",
        DATUM["New_Zealand_Geodetic_Datum_2000",
            SPHEROID["GRS 1980",6378137,298.257222101,
                AUTHORITY["EPSG","7019"]],
            TOWGS84[0,0,0,0,0,0,0],
            AUTHORITY["EPSG","6167"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4167"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",-36.87972222222222],
    PARAMETER["central_meridian",174.7641666666667],
    PARAMETER["scale_factor",0.9999],
    PARAMETER["false_easting",400000],
    PARAMETER["false_northing",800000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AUTHORITY["EPSG","2105"]]