I'm trying to use Black Planes for my mod but whenever I look at them in game or in the GECK's simulated in game lighting they do not appear. Any workarounds or alternate ways to achieve what I intend to do? I'm basically trying to use them to "Hide" the interior of my stone huts (Based of Industrial Pods) so that I can make them separate cells.

Black Planes? Your talking about those static objects that are used to hide sections of the local map aren't you? If I'm understanding you correctly, you want to block the player from viewing the inside of the pod while in an exterior cell, and have it so that the player enters an interior cell version of the pod which is decorated. Is this correct?

Yes exactly. I'm not too concerned about it looking awkward because I plan to cover it partially with Vain's Draqes. I think in that case I'll just make a big black decal.

The black planes must be 'above' the area you do not wish to see on the map. Anything that is above the black plane will render on the map.
It also must not be 'initially disabled'.

The black planes can be used to hide secret sections of an interior. Once the secret location is found, you disable the black plane and the secret section will then render on your map.

If you have a dirty save game where the area was already renderd on your map before you placed the black plane, then it may appear that the black plane is doing nothing.