This is how I would bleed your system, but I'm not a plumber just a jack of all trades and you know what that means
Close B, then close G. Then close D. Use valve c with a short piece of garden hose and a bucket and keep it kinked till you hear no more air coming out.
Then open G and D, close F, Close E , repeat the above. Then open everything back up.( Except C )I think thats it. Just two zones right??
You may be able to just close B and use C to bleed to whole system but I've never done it that way. My boiler is set up similarly and I've always seperated it and bled each zone on its own. Hey but what do i know I just kind of looked at mine and went for it, seemed to make sense. Good luck.