My code runs fine in a window but when I switch to full screen mode (<ALT><ENTER>) my panels no longer are overlayed but show the black areas and only 1/4 of the screen is covered. Any thoughts?

Maybe wrong file format, does this also happen with the panel from the tutorial?

I think since A7.80 (or maybe far before that) mode switching is restricted by the engine. It's recommended to set the fullscreen from the first run.

Nope. Look in the manual before telling strange nonsense to beginners, thats not helpful at all.

My mistakes... Ithough his fullscreen mode not running fullscreen, that happens to me, dunno why, maybe driver problem or something( I'm using A7 ver 7.80)...
But wrong file format will throw error at the first time right? maybe a sample of code will help...
Overlayed panel, is it using alpha channel or not?

Maybe he has used a bad format, like PNG or so, then the problem is clear. In supported formats like BMP TGA DDS, the alpha channel is preserved when switching to fullscreen, so this problem should not happen.

I'll have to check, but I believe the panel IS a PNG. Thanks for that... but even still the movie is only 1/4 of the whole screen. Unfortunately, I'm thinking a codec conflict because this code had worked fine in the past (several codecs added over the past several months)

Check also if your window resolution is supported in fullscreen. If not, you can't switch it to fullscreen no matter how hard you program. If it stays a window, your fullscree resolution is not supported and you must use video_switch again to switch it back to a supported resolution.