I am trying to run a DTI through the steps of tracula. I have trouble at 2 steps. This is the first one.
The problem doesn't happen if I am not attempting to set the following param in dmrirc:

set doregmni = 1

The command I am trying to run is: 
trac-all -prep -c dmrirc

Screen output is:exact screen output is:
Loading brain mask of output subject from /export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dlabel/mni/aparc+aseg_mask.nii.gz
Loading FA map of output subject from /export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/dtifit_FA.nii.gz
Loading affine registration from /export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms/mni2diff.bbr.mat
ERROR: File /export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms/mni2diff.bbr.mat must contain a 4x4 matrix
Linux jupiter 4.4.0-57-generic #78-Ubuntu SMP Fri Dec 9 23:50:32 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

trac-preproc exited with ERRORS at Mon Feb 12 06:54:15 MST 2018

Below I have printed out the contents of the file "mni2diff.bbr.mat"

jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir$ cd  /export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms
jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms$ ls
anat2anatorig.dat  anat2mni.mat           anatorig2diff.bbr.dat~         anatorig2diff.bbr.dat.param  anatorig2mni.mat       diff2mni.bbr.mat  mni2diff.bbr.mat
anat2anatorig.mat  anatorig2anat.mat      anatorig2diff.bbr.dat.log      anatorig2diff.bbr.dat.sum    diff2anat.bbr.mat      mni2anat.mat
anat2diff.bbr.mat  anatorig2diff.bbr.dat  anatorig2diff.bbr.dat.mincost  anatorig2diff.bbr.mat        diff2anatorig.bbr.mat  mni2anatorig.mat
jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms$ cat mni2diff.bbr.mat
*******
0x1.8969e5565d39cp-1  -0x1.030c103de571p-6  -0x1.ea2b581497ffap-13  0x1.e45ac50677f91p+5
-0x1.07d81a413710fp-9  0x1.974bb03bdcd16p-1  -0x1.e3d7b156202a6p-3  0x1.52b24a6f3ac76p+5
-0x1.35d1c0c40679ep-8  0x1.179efaa29fcbbp-2  0x1.1d5e96cd1e38bp-1  0x1.bae04d34dad4p+3
0x0p+0  0x0p+0  0x0p+0  0x1p+0
*******
jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir/tractDataDir/hbot_subj2/dmri/xfms$

The version of freesurfer:
jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir$ cat $FREESURFER_HOME/build-stamp.txt
freesurfer-Linux-centos6_x86_64-stable-pub-v6.0.0-2beb96c

the linux info
jtdavis@jupiter:/export/research/analysis/human/jlewine/shared/jtdavis/DataDir$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.1 LTS
Release:        16.04
Codename:       xenial