embed videos with greybox code

[slick33]

I have installed Greybox and made changes according to the instructions posted at the following link

Greybox for embed videos

It's not displaying the digg like thubnail video and its displaying the URL only not the video. I couldn't find any documentation to configure Greybox. Please help me to fix this problem.

The site is already configured for youtube video submission using simple tags.

Thanks,
SL