It does support 64 bits (I'm using it daily). You should have a 'VS2013 x64 Cross Tools Command Prompt' shortcut createdin C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\Tools\Shortcuts folder and that launches C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\vcvarsall.ba3 with x86_amd64 option.
To use it, set the QT_QPA_FB_DRM environment variable to a non-zero value. When set, provided that dumb buffers are supported by your system, legacy framebuffer Parameters like the device node name can be set in the environment variables QT_QPA_EVDEV_MOUSE_PARAMETERS...Set up Qt environment To compile/link/compile uic and moc, you must define the following environment variables to to point to Qt header files, Qt.lib, and Qt tools like moc.exe.