alignment ASL and t1w

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AFNI version info (afni -ver):
Precompiled binary linux_openmp_64: Jan 18 2021 (Version AFNI_21.0.04 'Titus')

Hi AFNI experts, 
I am attempting to coregister ASL to a skull stripped t1w image, and I have been having some trouble with alignment failing. The goal is to then align the coregistered ASL+t1w to MNI space. 
I have been running align_epi_anat.py with the following commands: 
align_epi_anat.py \
    -anat t1_ss.nii \
    -epi asl_orig.nii \
    -epi_base 1 \
    -epi2anat \
    -big_move \
    -partial_coverage \
    -cost lpa \
    -edge \
    -anat_has_skull no \
    -suffix _al

And this has worked for one or two participants, but the majority appear to have large misalignments, as you can see below. 
![Image 3-16-25 at 3.45 PM|647x500](upload://hD0f6C7TR9rgASisq3wLbCpAG7R.jpeg)
![Image 3-16-25 at 3.48 PM|495x500](upload://ipLmMnwc1xtpL0x4X0XQnaJNLRi.jpeg)

even modifying with -ginormous_move and -Allineate_opts ‘-maxrot 50’, the alignment still does not look good. Is there something I am missing? 
Thanks so much, 
MK
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Image 3-16-25 at 3.45 PM
Image 3-16-25 at 3.45 PM818×632 60.9 KB

Image 3-16-25 at 3.48 PM
Image 3-16-25 at 3.48 PM656×662 56.4 KB

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Try a different cost function like "-cost nmi". I don't think you need to modify the 3dAllineate options here. If you can't get it to work, see if you can send me some data, and I'll try to take a look.