Remember to pull it with --recursive to pick up the submodules. Example:

git clone --recursive https://github.com/SpringCabal/Hunted.git Hunted.sdd

Make sure you have git configured to automatically fetch submodules:

git config --global fetch.recurseSubmodules true

Use engine from: https://springrts.com/dl/buildbot/default/ld33_prep/100.0.1-1-gffd50a7/