You are obviously executing this in the wrong path.
The last part command tells cmake to look for the CMakeLists.txt file in the parent directory of where you currently are.
And apparently that parent directory is G:/Qt/Qt5.0.2/5.0.2/msvc2010 and not G:\KDE
You probably want to do
cd %KDELIBPATH%
before the mkdir command, i.e. create the build directory inside the source directory
Cheers,
_
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