Hi everyone.  This is Jared over at Brigham and Women's.   I have a follow-up question on the question I asked earlier about automating TkMedit such that it will switch between the segmentation overlay view and the gray-scale MRI view automatically.  I was able to find a scripting option that I believe should allow me to switch the view from a command-line prompt.  The command is listed in the TkMedit Guide.  It is "SetDisplayFlag flag value" where flag is equal to one of various display options and value is equal to 0 or 1, presumably on or off.  We use Mac OS X and run freesurfer through the Terminal command prompt using X11 as our graphical display program.  Anyway, when I enter the command "SetDisplayFlag 15 1" which I believe should do the same thing as the keystroke control-g (turn on the segmentation overlay) my command prompt shows me no error messages, apparently accepts the command, but nothing changes on my display.  The view remains exactly as it was before regardless of whether or not the segmentation volume was initially on or off when I ran the command.    If anyone knows how to turn the segmentation overlay on or off from a command prompt or can correct any missteps that I may have taken please let me know. 
Thanks and all the best to each of you,

Jared Price
Center for Neurological Imaging
Brigham and Women's Hospital
Harvard Medical School
1249 Boylston Street
Boston, MA 02115

617-525-6076
jcp44@bwh.harvard.edu