TL;DR: On Windows with Visual Studio, Remove CMakeCache.txt and rerun CMake.
I've fixed a problem with the build just ignoring the BUILD_WITH_CXX build setting - however it means that unless you remove that cached setting and run cmake again or just run cmake from scratch you will get errors in your Windows builds because the default and stored version of BUILD_WITH_CXX was previously NO on all platforms. Sorry for any inconvenience. Andrew
