Frame markers, sizes and videos?

Hello,

We are working on a small video app using Vuforia in Unity 5.

Currently we have managed to generate markers and with help of the image and video prefabs get videos to pop up and play on our custom markers.

However, when we try and use the frame markers that are inside vuforia, our videos just show up as white squares, why is that? We have added on the video prefab just as on previous mentioned markers. Do we have to make anything special for our videos to play on the frame marker?

Also, in order to make our videos bigger than the markers when they are being played on a phone, do we just need to resize the video prefab?

Regards

Intermedia