It turns out that the segmentation is fine in aseg.mgz (although for some reason I am unable to view the segmentation with FreeSurferColorLUT.txt as it says it wasn't valid or wasn't found even though it is in my directory) and yet the aseg.stats table was not generated.
(Doug?) How does one generate a table if the aseg.mgz file is accurate but the aseg.stats file is not?
Many thanks, Joan