I almost gave up on openEMS because building it was a challenge at first. With enough digging through the forums and experimenting, I finally got it going. I present here the recipe for building on Linux Mint 19.1 - I've tried this on a fresh install in a VM, and it works. If all else fails on your platform of choice, you can always spin up a Mint VM yourself and work in there.
sudo apt-get install autogen autoconf libtool automake autotools-dev build-essential git cmake libhdf5-dev libvtk6-dev libboost-all-dev libcgal-dev libtinyxml-dev libqt4-dev libvtk6-qt-dev libhpdf-dev gengetopt git clone --recursive https://github.com/thliebig/openEMS-Project.git cd openEMS-Project/ ./update_openEMS.sh ~/opt/openEMS --with-hyp2mat --with-CTB --with-MPI
You will also need to install GNU Octave and ParaView, but those are in the package repos.