External Email - Use Caution        

On MacOS I would try running the fs_install_mcr script with,

$ export FREESURFER_HOME=/Applications/freesurfer/7.3.2

$ source $FREESURFER_HOME/SetUpFreeSurfer.sh

<... output showing SUBJECTS_DIR and other environment variables>

$ cd  $FREESURFER_HOME/bin

$ sudo FREESURFER_HOME=$FREESURFER_HOME  ./fs_install_mcr  R2014b

That script should setup the environment to find the libmwm* libraries it installs in the freesurfer tree under $FREESURFER_HOME/MCRv84/bin/glnxa64.

But If your shell environment (e.g., via $HOME/.cshrc or $HOME/.bashrc) somehow sets LD_LIBRARY_PATH to point to a different matlab installation, then you may not pick up the matlab distribution from the freesurfer tree.

- R.