[Freesurfer] Cutting closed line for flat map

I'm trying to cut the medial wall as described in Step 2 on http://surfer.nmr.mgh.harvard.edu/fswiki/FreeSurferOccipitalFlattenedPatch . However, each time I click "Cut Closed Line", I get a jumble of lines that go all over the cortex and medial wall, rather than a clean circle around the medial wall. I've tried putting cut points so close that they're nearly on top of each other, but it still doesn't help.

Does anyone have an idea why this won't cut right?

Thanks, --Greg

____________________________________________________________________ Greg Burgess, Ph.D. Staff Scientist, Human Connectome Project Washington University School of Medicine Department of Anatomy and Neurobiology Email: burgessg@pcg.wustl.edu