My tracula completed with no error. So I was trying to view the fa.nii with the following command:

freeview -v mri/brain.mgz  mri/orig.mgz mri/wmparc.mgz:colormap=lut:opacity=0.2 dmri/dtifit_FA.nii:reg=touch/rusage.mri_ca_register.dat:colormap=heat:heatscale=.2,.2,1 -colorscale -viewport coronal. 

It returned with an error message saying: "reading registration failed". I have looked at the register.dat from the following link: RegisterDat - Free Surfer Wiki (harvard.edu). My register.dat is nothing like that (attached below). So where should the file locate?

Best, 

Jackie