Forgive my ignorance here but are you suggesting that CMake should give the the .lib file directly? Or rather that using the parameter you suggested, I will get VS files that might then lead to building the '_d.lib' flavour I need?
At work now, so going to have to try your idea at home.
Edit:Managed to try it during my lunch. I just get the following message after it has done all it's stuff:
Manually-specified variables were not used by the project:
Perhaps I'm misunderstanding something here. When building in debug say the 'HelloWorld' box2d example, does it output a debug library? It must do right?