Commands to install Pangolin should include sudo git submodule update --init as follows:
# install Pangolin
git clone git@github.com:stevenlovegrove/Pangolin.git
cd Pangolin
sudo git submodule update --init
git checkout d484494 # this is the most recent commit that worked for everything
mkdir build
cd build
cmake ..
make -j
sudo make install
Commands to install Pangolin should include
sudo git submodule update --init
as follows: