I have three questions:

1) If the gretchin crew goes to ground and are in the next round rallied again, should they be regarded as if having moved and thus be unable to fire the big gunz or are they free to fire at will?

2) In the Ork faq there is nothing said about Zzap gunz ability to roll four (2+2) D6 when attacking vehicles. It just says that they are regarded as artillery, and a statline with str 2D6. Do they still get to roll those two dice in armour penetration also?

3) If the only remaining figure in a battery is the slaver (and a big gun), is he allowed to fire the gun or does it have to be a gretchin?