Rogue Leader said:

never noticed it before but what's the blinking red light out side the door when the get it open to the landing pad on the ground? When the camera switches view the light is no longer there... what the hell is it?

Ah, you've brought up a little something I was intending to go into soon (with screenshots) to do with this particular aspect.

I reckon that pool of flashing red light that shows on the ground when R2 opens the doorway is supposed to be....the reflection of the flashing red light that is seen in-between the 2 white lights directly outside the top of the exterior of these doorways.

That's my take on it anyway, as the flashing red (middle) light above the doorways can be seen in some of the shots where we first see Lando greet our heroes, and when Leia and Chewie just miss Slave 1 taking off. I was going to ask if adywan could subtly include it in-between the 2 white doorway lights on his very nicely-coloured shot of the Bespin building where the stormtroopers come out firing, as it still seems to be missing.

Thing is, the point where R2 initially opens the door leading to the Falcon seems to be the only shot where any kind of red flashing 'reflection' was introduced. Although the small flashing middle red lights are unlikely to cast such an impressive 'reflection' on the ground, I kinda think it works okay 'stylistically' in that particular shot. But it could be that I'm just used to seeing it over the years.... ;)