I'm assuming PlanetaryFunk is referring to building the
actual Box2d library for C/C++, not the DBP plugin (otherwise he would have just d/loaded the plug-in, presumably)
Unfortunately I can't help: I faced the exact same problem. CMake refused to build it on Windows. I ended up just compiling via command line (still using CMake) on OS X which worked fine.
EDIT: Talking of which, doesn't DBP's plugin violate Box2d's licence? zlib licence states " The origin of this software must not be misrepresented" - calling the plugin the exact same name as the actual engine does exactly that in my opinion (as it implies it is
the Box2d, not just a wrapper). Also leads to confusion, as per this thread
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