Uniy-DK2 Integration/ Unity build up demo

Hello,
I'm a master student from Jordan, I have a problem in unity-Dk2 integration .. when I press build from file- build settings .. the outcome just and exe file and when I play it ..It runs with a one window not tow windows like the pre-build demo attached with oculus SDK which affect oculus display .. So what can I do in this manner? ;)