The env variables I listed are directories, not specific dsets. Which env variables are you referring to, specifically?
I would unpack NMT2 dsets into the directory I want to use as a global session (e.g,. /home/username/REF_TEMPLATES), and then refer to the full REF_TEMPLATES path.
The NMT contains different sets of data (the fullhead, the 0.5mm resolution, etc.). Each of those sets of dsets has different names, I believe:
NMT_v2.0_sym_05mm/CHARM_in_NMT_v2.0_sym_05mm.nii.gz
NMT_v2.0_sym/CHARM_in_NMT_v2.0_sym.nii.gz
NMT_v2.0_sym_fh/CHARM_in_NMT_v2.0_sym_fh.nii.gz
.. so those CHARM* could all be unpacked into a single directory. There should be no ambiguity amongst those filenames.
--pt