I am trying to extract CC subregion labels from aparc+aseg.mgz (ids: 251-255) into a format that is compatible with MNI space in FSL. I was planning on extracting CC labels and then converting the labels from fsaverage space to MNI space. I first tried to extract the 5 separate CC labels using the command: mri_vol2label --c aparc+aseg.mgz --id 255 --l 255.label. When viewed in FreeView, the labels were spotty looking. Did I do this mgz to label extraction correctly?

And also do you have a recommended code to convert FreeSurfer CC subregions into MNI space ROIs for FSL?