Use of stereoscopic 360 degrees videos in UE4

I am trying to play a stereo 360 video (512x512), and i follow this steps; i create a sphere mesh with inverted normals and i made the material for the video, but it doesn’t work… instead with the mono video works.
In the materia that i create for the 360 stereo video (following the material posted in this topic) i cannot see the preview in the texture sample…
Someone can help me?