Hi Matt.
1. You make all the Combat Moves you want, then when you tell your opponent you are ready you choose which one you want to do roll for first, then choose a second etc.
All have to be declared at once. You cannot add more attacks later.
2. Aircraft Carriers can be attacked with or without planes and they defend on a “2”; they just do not have an attack value. They can go into a hostile Sea Zone with other units as long as one of them has an attack value and then you could take two hits on the Carrier if you did not mind losing one.( They do defend better if they have planes on them.)
3. A Sub can submerge if the other side does not have a Destroyer. It submerges instead of defending. If a Sub chooses to submerge against your Battleships then the attacker could not bombard, as it had commited to killing the Subs. (Do not try and attack Subs without a Destroyer, they will submerge!) in your scenario, just bombard and ignore the Subs, or make sure you always have one Destroyer with your fleet.
3. Submarines. They can submerge at any time? If they submerge is that considered combat, or can your units move in the Noncombat move phase?
Not sure what you are asking here ,sorry!
4. Yes. Up to you how you roll, so long as your opponent is aware of what you are doing.
5. Yes, when you capture the Capital, you get the money they have on them.