You should be able to build Calitko using Visual Studio .NET and 2005. The compiler coming along with Visual Studio 6.0 is too old and will not want to compile all of the Calitko source code. If you do not have a commercial license for Visual Studio, you can download the free Express version from http://msdn.microsoft.com/vstudio/express/visualc/download/. Make sure you also install the free Platform SDK. Follow the instructions at http://msdn.microsoft.com/vstudio/express/visualc/usingpsdk/.
The latest version of Qt/Windows (OpenSource) can be downloaded from http://www.trolltech.com/developer/downloads/qt/windows. Chose a mirror to download the file qt-win-opensource-src-4.x.x.zip. It contains the complete source code of Qt.
Follow the instructions at http://qtnode.net/wiki/Qt4_with_Visual_Studio in order to build Qt using MSVS.
If you did everything right you'll be ready to build Calitko!