It is almost impossible to understand what you want to achieve.
Why do you want to scale the panel when it is bigger than the resolution anyway?
If you want to play a video within the game then you don't need a panel:
From the online manual:
http://www.conitec.net/beta/amedia_play.htm"target
C Pointer to a bmap that serves as target texture for the video stream, or NULL for playing the video in the whole engine window. Using a target texture, the video can be played on a model or sprite surface in the level."