Help needed with Launchpad double buffering

Originally posted in the max-msp section, but no response! I'm hoping that perhaps someone here will be able to help, or at least point me in the right direction!

I'm trying to set up a Launchpad to use with Max (not max4live), and there's a few conceptual holes I have that need filling! (I've tried just playing around, but I'm not getting anywhere).

I've got turning LEDS on and off working ok, but now I'm trying to use double buffering, and I can't figure out the whole "setting bits" thing in terms of midi numbers.

I need to set the copy and clear bits to zero. I think that this relates to the velocity formula, which is given as

Velocity = (16*Green)+Red+Flags
Flags are 12 (normal use), 8 (flashing) 0 (for double buffering)

So I guess the first question is - what the heck values do "Green" and "Red" represent? The docs say:
Bit 5..4 - Green = Green LED brightness
Bit 1..0 - Red - Red LED brightness
but I don't see what that has to do with the formula.

Unfortunately the Launchpad developer docs don't give any practical examples of how to go about doing this, and I haven't been able to find any help on Novation or Ableton's sites. (There's a demo sequencer on the Novation site, but it only opens in max4live, so it's no use to me for figuring out how to do this).

Any pointers, hints or other help greatly appreciated!

thanks

David