It's slightly off topic, but begging your leave: If there is anyone out there who is experienced in amira, and might be willing to offer a little email help for a very tricky segmentation, I'd be very grateful. The segmentation is for use with freesurfer, at least, so it's not a total outrage to ask I hope.
best,
Colin Reveley, Sussex
freesurfer@nmr.mgh.harvard.edu