MRtrix3Tissue ss3t_csd_beta1 not running

Hi all, I have installed MRtrix3Tissue and set the path to it in my my .zsh startup file.
The path to the MRtrix3Tissue directory is /Users/myusername/MRtrix3Tissue.
The path to the python3 directory is /usr/local/bin/python3.
I have created a directory named python and linked it to python3 using sudo ln -s /usr/local/bin/python3 /usr/local/bin/python (otherwise I would get env: python: no such file or directory every time I tried to run a command.

When I run the command mrinfo I indeed get:

~ % mrinfo
MRtrix 3Tissue_v5.2.9                mrinfo                          Oct 31 2024

     mrinfo: part of the MRtrix3 package

SYNOPSIS

     Display image header information, or extract specific information from the
     header

USAGE

     mrinfo [ options ] image [ image ... ]

        image        the input image(s).


DESCRIPTION

     By default, all information contained in each image header will be printed
     to the console in a reader-friendly format.

     Alternatively, command-line options may be used to extract specific
     details from the header(s); these are printed to the console in a format

Despite this if I try to run ss3t_csd_beta1 I get: env: python: Permission denied.
If I check the ownership of the files in the bin directory of MRtrix3Tissue I get:

ls -l ~/MRtrix3Tissue/bin
total 105448
-rwxr-xr-x  1 root            staff   258400 31 Ott 01:49 5tt2gmwmi
-rwxr-xr-x  1 root            staff   239584 31 Ott 01:42 5tt2vis
-rwxr-xr-x  1 root            staff   253488 31 Ott 01:50 5ttcheck
-rwxr-xr-x  1 root            staff   256496 31 Ott 01:48 5ttedit
-rwxr-xr-x  1 myusername  staff     3026 18 Ago 23:33 5ttgen
drwxr-xr-x  3 myusername  staff       96 31 Ott 18:46 __pycache__
-rwxr-xr-x  1 root            staff  1185144 31 Ott 01:57 afdconnectivity
-rwxr-xr-x  1 root            staff   425176 31 Ott 01:59 amp2response
-rwxr-xr-x  1 root            staff   497072 31 Ott 01:53 amp2sh
-rwxr-xr-x  1 myusername  staff     1619 18 Ago 23:33 blend
-rwxr-xr-x  1 root            staff   599096 31 Ott 01:58 connectome2tck
-rwxr-xr-x  1 root            staff   359608 31 Ott 01:49 connectomestats
-rwxr-xr-x  1 myusername  staff     3689 18 Ago 23:33 convert_bruker
-rwxr-xr-x  1 root            staff    75088 31 Ott 01:45 dcmedit
-rwxr-xr-x  1 root            staff    75976 31 Ott 01:59 dcminfo
-rwxr-xr-x  1 root            staff   129152 31 Ott 01:45 dirflip
-rwxr-xr-x  1 root            staff   148680 31 Ott 01:51 dirgen
-rwxr-xr-x  1 root            staff   103296 31 Ott 01:58 dirmerge
-rwxr-xr-x  1 root            staff   113512 31 Ott 01:50 dirorder
-rwxr-xr-x  1 root            staff   130392 31 Ott 01:53 dirsplit
-rwxr-xr-x  1 root            staff   304800 31 Ott 01:47 dirstat
-rwxr-xr-x  1 root            staff   279088 31 Ott 01:50 dwi2adc
-rwxr-xr-x  1 root            staff   689800 31 Ott 01:48 dwi2fod
-rwxr-xr-x  1 root            staff   540072 31 Ott 01:54 dwi2mask
-rwxr-xr-x  1 myusername  staff     5351 18 Ago 23:33 dwi2response
-rwxr-xr-x  1 root            staff   323032 31 Ott 01:54 dwi2tensor
-rwxr-xr-x  1 myusername  staff     2749 18 Ago 23:33 dwibiascorrect
-rwxr-xr-x  1 myusername  staff     6515 18 Ago 23:33 dwicat
-rwxr-xr-x  1 root            staff   835992 31 Ott 01:47 dwidenoise
-rwxr-xr-x  1 root            staff   226448 31 Ott 01:59 dwiextract
-rwxr-xr-x  1 myusername  staff    71898 18 Ago 23:33 dwifslpreproc
-rwxr-xr-x  1 myusername  staff     7883 18 Ago 23:33 dwigradcheck
-rwxr-xr-x  1 myusername  staff     1419 18 Ago 23:33 dwinormalise
-rwxr-xr-x  1 myusername  staff     2732 18 Ago 23:33 dwishellmath
-rwxr-xr-x  1 root            staff   232504 31 Ott 01:53 fixel2sh
-rwxr-xr-x  1 root            staff   875872 31 Ott 01:51 fixel2tsf
-rwxr-xr-x  1 root            staff   589176 31 Ott 01:51 fixel2voxel
-rwxr-xr-x  1 root            staff  1212960 31 Ott 01:59 fixelcfestats
-rwxr-xr-x  1 root            staff   350976 31 Ott 01:59 fixelconvert
-rwxr-xr-x  1 root            staff   292392 31 Ott 01:51 fixelcorrespondence
-rwxr-xr-x  1 root            staff   276960 31 Ott 01:54 fixelcrop
-rwxr-xr-x  1 root            staff   297112 31 Ott 01:49 fixelreorient
-rwxr-xr-x  1 root            staff   446528 31 Ott 01:44 fod2dec
-rwxr-xr-x  1 root            staff   602352 31 Ott 01:45 fod2fixel
-rwxr-xr-x  1 myusername  staff    15726 18 Ago 23:33 foreach
-rwxr-xr-x  1 myusername  staff     4457 18 Ago 23:33 gen_scheme
-rwxr-xr-x  1 root            staff   282968 31 Ott 01:44 label2colour
-rwxr-xr-x  1 root            staff   515544 31 Ott 01:46 label2mesh
-rwxr-xr-x  1 root            staff   298424 31 Ott 01:58 labelconvert
-rwxr-xr-x  1 myusername  staff     8784 18 Ago 23:33 labelsgmfix
-rwxr-xr-x  1 root            staff   132088 31 Ott 01:53 maskdump
-rwxr-xr-x  1 root            staff   316416 31 Ott 01:58 maskfilter
-rwxr-xr-x  1 root            staff   556216 31 Ott 01:47 mesh2voxel
-rwxr-xr-x  1 root            staff   413376 31 Ott 01:59 meshconvert
-rwxr-xr-x  1 root            staff   430528 31 Ott 01:51 meshfilter
-rwxr-xr-x  1 root            staff   643928 31 Ott 01:53 mraverageheader
-rwxr-xr-x  1 root            staff   443440 31 Ott 01:45 mrcalc
-rwxr-xr-x  1 root            staff   499344 31 Ott 01:46 mrcat
-rwxr-xr-x  1 root            staff   127728 31 Ott 01:54 mrcheckerboardmask
-rwxr-xr-x  1 root            staff   511752 31 Ott 01:45 mrclusterstats
-rwxr-xr-x  1 root            staff   352432 31 Ott 01:52 mrcolour
-rwxr-xr-x  1 root            staff   877096 31 Ott 01:45 mrconvert
-rwxr-xr-x  1 root            staff   188800 31 Ott 01:50 mrdegibbs
-rwxr-xr-x  1 root            staff   496280 31 Ott 01:46 mrdump
-rwxr-xr-x  1 root            staff   145392 31 Ott 01:52 mredit
-rwxr-xr-x  1 root            staff   457512 31 Ott 01:50 mrfilter
-rwxr-xr-x  1 root            staff   439680 31 Ott 01:44 mrgrid
-rwxr-xr-x  1 root            staff   226080 31 Ott 01:45 mrhistmatch
-rwxr-xr-x  1 root            staff   157288 31 Ott 01:58 mrhistogram
-rwxr-xr-x  1 root            staff   212992 31 Ott 01:49 mrinfo
-rwxr-xr-x  1 root            staff  1425712 31 Ott 02:00 mrmath
-rwxr-xr-x  1 root            staff   929624 31 Ott 01:52 mrmetric
-rwxr-xr-x  1 root            staff  3884544 31 Ott 01:52 mrregister
-rwxr-xr-x  1 root            staff   172152 31 Ott 01:45 mrstats
-rwxr-xr-x  1 root            staff   596408 31 Ott 01:58 mrthreshold
-rwxr-xr-x  1 root            staff  1361072 31 Ott 02:00 mrtransform
-rw-r--r--  1 myusername  staff     1730 18 Ago 23:33 mrtrix3.py
-rwxr-xr-x  1 root            staff  3140696 31 Ott 01:57 mrview
-rwxr-xr-x  1 root            staff   466712 31 Ott 01:51 mtnormalise
-rwxr-xr-x  1 myusername  staff      835 18 Ago 23:33 notfound
-rwxr-xr-x  1 root            staff   109184 31 Ott 01:50 peaks2amp
-rwxr-xr-x  1 myusername  staff    40007 18 Ago 23:33 population_template
-rwxr-xr-x  1 myusername  staff     4482 18 Ago 23:33 responsemean
-rwxr-xr-x  1 root            staff   320224 31 Ott 01:42 sh2amp
-rwxr-xr-x  1 root            staff   277504 31 Ott 01:57 sh2peaks
-rwxr-xr-x  1 root            staff   153800 31 Ott 01:59 sh2power
-rwxr-xr-x  1 root            staff   269816 31 Ott 01:43 sh2response
-rwxr-xr-x  1 root            staff   302024 31 Ott 01:53 shbasis
-rwxr-xr-x  1 root            staff   241040 31 Ott 01:50 shconv
-rwxr-xr-x  1 root            staff   617872 31 Ott 01:47 shview
-rwxr-xr-x@ 1 root            group    15030 18 Ago 23:33 ss3t_csd_beta1
-rwxr-xr-x  1 root            staff   607936 31 Ott 01:46 tck2connectome
-rwxr-xr-x  1 root            staff  1008200 31 Ott 01:51 tck2fixel
-rwxr-xr-x  1 root            staff   432272 31 Ott 01:45 tckconvert
-rwxr-xr-x  1 root            staff   989120 31 Ott 01:59 tckdfc
-rwxr-xr-x  1 root            staff   347984 31 Ott 01:50 tckedit
-rwxr-xr-x  1 root            staff  2020976 31 Ott 01:53 tckgen
-rwxr-xr-x  1 root            staff   674592 31 Ott 01:48 tckglobal
-rwxr-xr-x  1 root            staff   220624 31 Ott 01:53 tckinfo
-rwxr-xr-x  1 root            staff  1663232 31 Ott 01:45 tckmap
-rwxr-xr-x  1 root            staff   371640 31 Ott 01:43 tckresample
-rwxr-xr-x  1 root            staff   919112 31 Ott 01:59 tcksample
-rwxr-xr-x  1 root            staff  1553920 31 Ott 01:43 tcksift
-rwxr-xr-x  1 root            staff  1534936 31 Ott 01:52 tcksift2
-rwxr-xr-x  1 root            staff   242520 31 Ott 01:43 tckstats
-rwxr-xr-x  1 root            staff   358176 31 Ott 01:42 tcktransform
-rwxr-xr-x  1 root            staff   282224 31 Ott 01:50 tensor2metric
-rwxr-xr-x  1 root            staff   359552 31 Ott 01:44 transformcalc
-rwxr-xr-x  1 root            staff   216648 31 Ott 01:58 transformcompose
-rwxr-xr-x  1 root            staff   123928 31 Ott 01:42 transformconvert
-rwxr-xr-x  1 root            staff   223048 31 Ott 01:51 tsfdivide
-rwxr-xr-x  1 root            staff   201656 31 Ott 01:51 tsfinfo
-rwxr-xr-x  1 root            staff   223048 31 Ott 01:47 tsfmult
-rwxr-xr-x  1 root            staff   205624 31 Ott 01:45 tsfsmooth
-rwxr-xr-x  1 root            staff   205424 31 Ott 01:53 tsfthreshold
-rwxr-xr-x  1 root            staff   221312 31 Ott 01:45 tsfvalidate
-rwxr-xr-x  1 root            staff   177784 31 Ott 01:43 vectorstats
-rwxr-xr-x  1 root            staff   234528 31 Ott 01:59 voxel2fixel
-rwxr-xr-x  1 root            staff   548920 31 Ott 01:57 voxel2mesh
-rwxr-xr-x  1 root            staff   310728 31 Ott 01:44 warp2metric
-rwxr-xr-x  1 root            staff   300744 31 Ott 01:58 warpconvert
-rwxr-xr-x  1 root            staff   190440 31 Ott 01:45 warpcorrect
-rwxr-xr-x  1 root            staff   148552 31 Ott 01:52 warpinit
-rwxr-xr-x  1 root            staff   196032 31 Ott 01:44 warpinvert

Do you have any suggestion to solve this problem?

Thank you.

Solved by installing an older version of python (3.9.10, newer versions might work as well) and setting it for usage in the MRtrix3Tissue directory using pyenv local. It seems that the python 3.13 I have installed does not have the command python invoked by MRtrix3Tissue, but instead has python3.

I tried setting an alias with alias python=python3 but failed.