remote sensing - LANDSAT 8 i.landsat.toar error GRASS 7

I am a bit new to GRASS, but I have managed to get a lot of good work done thus far. However, the following error is really throwing me off, because I can't find any help anywhere for it. I am using GRASS 7 that I downloaded today (9.23.13) on Windows 7.

Basically, I have a set of bands from a new Landsat 8 image acquired in May 2013. I want to convert these (GeoTiff format) to Top-of-Atmosphere using i.landsat.toar. According to what I've read, this should be the tool to use. I have the metadata file for the imagery and have made sure that i.landsat.toar is accessing it and that the computational region is set. However, I'm getting the following TWO errors.

Note this is the output from the tool's dialog box.

Error 1: The tool appears not to be picking up the Earth-sun distance or the Solar elevation angle from the metadata file

i.landsat.toar --overwrite --verbose input_prefix=LC80630462013143LGN01_B output_prefix=TOAR2_ metfile=C:\Users\Andrew\Desktop\All Projects\PTA\Mapping\Landsat\LC80630462013143LGN01_MTL.txt sensor=ot8

    Metada file is MTL file: new format
    RADIANCE & QUANTIZE from data of the metadata file

    ESUN evaluate from REFLECTANCE_ADDITIVE_FACTOR_BAND of the metadata file
     LANDSAT: 8 SENSOR: OLI/TIRS
     ACQUISITION DATE 2013-05-23 [production date 2013-05-28]
       Earth-sun distance    = 0.00000000
       Solar elevation angle = 0.00000000
       Atmospheric correction = UNCORRECTED

Error 2: Because of this (?) it thinks that BAND 1 (and all the rest of the bands) have calibrated DN's in the range 0 to 0.

     BAND 1  (code 1)
       calibrated digital number (DN): 0.0 to 0.0

       calibration constants (L): -0.000 to 0.000
       at-sensor radiance = -0.00000000 * DN + -0.000
       mean solar exoatmospheric irradiance (ESUN): -0.000
       at-sensor reflectance = radiance / -0.00000
    -------------------
     BAND 2  (code 2)
       calibrated digital number (DN): 0.0 to 0.0
       calibration constants (L): 330444430637036151551722492294
    587268563145980464374645729863366094385568172627644951713179
    378481117952893338397577640994585275959535639861949498028426

    262590359799651950264727525610431453748910545956564791713413
    700827628649921419448208128081385936515331098210632350384577
    822089022182894321784571544979905732238361760724622021578607
    979232195464053310102313472742663525983586004143091065701111
    514715113697333585943053423533112929011860884077135607428377
    220404697113400382954102158210112807905333778313832237152143
    633839279456924366120960750591866213481411548079987319784626
    444589368787016457003827891606484279320248476371919970747319
    49817417372212139642585088.000 to 0.000
       at-sensor radiance = -0.00000000 * DN + -0.000

       mean solar exoatmospheric irradiance (ESUN): 0.000
       at-sensor reflectance = radiance / -0.00000