Hi Aimee,
What do you mean when you say the images are scrambled?
Are they out of order, or does each slice look fuzzy? If
each slice image looks fuzzy, you may want to try the
"Byte swap" button.
You probably want to use -time:zt instead of -time:tz.
That means that in your input file, the slices for a single
volume are together sequentially, which is most likely the
case.
Also, though it won't affect the result at all, you might
enjoy using '-xFOV 100R-L', instead of '-xFOV 100R-100L',
assuming slices are centered about zero.
I hope some of this helps... :)
- rick