Question 1: Anytime all the ability is removed from the a battle (either because the character/starship is immediately lost or via cards like Clash of Sabers/You Are Beaten, Blast The Door Kid, Set For Stun, etc.) the battle immediately ends. And because those actions can only occur during the weapons phase there is no battle destiny drawn or totalling of power. Any 'hit' cards are still lost. Question 2: The amount can vary depending on the amount of sites at the Rebel Base and whether or not you are using the SYCFA objective. See Commence Primary Ignition for how to calculate the Force loss.