[Freesurfer] Cannot view average curvature after make_average_subject

Hi all, I'm setting up a small study where I want to compare a subject to some matched controls. I've been following the Group analysis tutorial and I've run make_average_subject on my controls. Now, I'd like to check my data and view averaged curvature and thickness measurements. When I try to load the lh.avg_curv onto lh white in tksurfer, I get the following error: ERROR: number of vertices in XX/lh.avg_curv does not match surface (173612,163842)surfer: error reading curvature file The same applies to lh.avg_thickness However, there is a file called lh.curv that I can load. What am I doing wrong here? How can I view the average curvature and thickness measurements? Thanks a lot everyone, Johannes