as on GitHub:
git clone firstname.lastname@example.org:ivansafrin/Polycode.git
git checkout origin/goodbye_cmake
git submodule update --init "lib"
then open the build/windows/win32/Polycode.sln - do not upgrade them on startup. Then you may have to apply the changes mentioned in the GitHub issue: https://github.com/ivansafrin/Polycode/issues/707#issuecomment-247978988
and then you may build the whole solution in Debug and or Release (as you wish). The IDE is called Polycode Studio and can be found in build/windows/win32/Release.
For use with C++ you can finde the library files in the respective folders in lib - but be aware that here windows means Universal Windows Project and win32 is the usual windows application stuff.
All the needed header files are in include. You should use
#include <Polycode.h> in files using standard polycode stuff.