This was posted in the material room bookmarks thread.

I thought I would move it here so that he can get an answer to his question:

PLEASE HELP MEEEEE! I'm stuck in the Material room. 

After three hours spent creating a figure which looks perfect in preview, every time I render it in the Material Room it goes to a barely defined yellow sillhouette. I've disconnected all the nodes and tried to start from scratch - but the render still blasts all the detail.

Is there a magic button somewhere called WYSIWYG which realigns all Material Room parameters to erase all the mistakes I MIGHT have made and makes the render look like the preview?????

Infinite thanks for any help provided......  

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi