Hi, Fabian-
Thanks for the further details. I think there are 2 things going on here:
+ your dataset was acquired with the macaque in sphinx position (so, where the "axial" brainslices of a human brain would be, there are now upside-down coronal views; etc.).
+ your dataset was acquired with obliquity (so there is a rotation+translation of the FOV relative to "scanner coords").
These are manageable; it might be easier if I take a look at the dataset in question. I will send you an email to upload the data, if possible.
--pt
