[Snapshot and r5-tk]

No, Snap Shot specifies that an enemy ship must be the target.

[Shattering Shot - when do you spend the force to add the eyeball?]

Adding results (a focus result, in this case) is a dice modification.  Shattering Shot occurs during step 2b of Attack (Modify Attack Dice) which is after rolling dice.

[Hate & Chancellor Palpatine crew timing]

Hate occurs before Palpatine.

Hate occurs in step 5 of attack (Deal Damage).  Chancellor Palpatine occurs in step 6 (Aftermath).

[ST-321 timing with boost/barrel roll]

The ST-321 lock acquisition occurs after the coordinated ship performs (or fails) the coordinated action.  That action is part of Coordinate (step 3).  ST-321 resolves after that, and you would thus measure from the post-boost position of the coordinated ship.

[Kanan Crew Ability]

Yes, as long as the range requirement is met, and the Force is paid.

Kanan Jarrus (VCX-100): "After a friendly ship at range 0-2 fully executes a white maneuver, you may spend 1 [Force] to remove 1 stress token from that ship."

Furthermore, if a ship executes a white maneuver onto or through a debris cloud, Kanan would be able to remove the ensuing stress, permitting that ship to take their Perform Step action.

[Seismic Charges and Proximity Mines Interaction]

You are correct.  Proximity Mines are not obstacles, and do not interact with Seismic Charges.

[Moralo interaction with tokens]

All tokens accompany ships into reserve.  Circular tokens are removed during the End Phase.  When a ship in reserve is placed in the play area, any tokens on the ship accompany it into play.

[Malarus (FO) and Muse]

Not quite.  Ships do engage in descending initiative order, but all "At the start of the Engagement Phase" happen before ships actually engage, and enter the ability queue simultaneously.  But yes, you may resolve Commander Malarus' (TIE/fo Fighter) ability, and then Muse's (TIE/fo Fighter) ability to remove the stress Malarus just gained.

[Shasa Zaro and Reinforce Tokens]

When a ship performs the reinforce action, it gains a reinforce token with either the fore or aft side faceup. When transferring or gaining a "matching" reinforce token, you must maintain the original orientation.

 

[B-Wing Hera with Weapon Systems Officer and Stabilized S-Foils lock interactions]

No, the sequence in your example is not quite correct.

The Aftermath rules ("after you perform an attack") are as follows:

6. Aftermath: Abilities that trigger after an attack are resolved in the following order.
a. Resolve any of the defending player’s abilities that trigger after a ship defends or is destroyed, excluding abilities that grant a bonus attack.
b. Resolve any of the attacking player’s abilities that trigger after a ship performs an attack or is destroyed, excluding abilities that grant a bonus attack.
c. Resolve any of the defending player’s abilities that trigger after a ship defends or is destroyed that grant a bonus attack.
d. Resolve any of the attacking player’s abilities that trigger after a ship performs an attack or is destroyed that grant a bonus attack.

Applying this to your example:

-The B-Wing attacks with Plasma Torpedo.  (She should spend the lock as Weapon Systems Officer will grant it back.)
-6b. Weapon Systems Officer resolves.
-6d. The B-Wing has the opportunity to spend a lock to perform a bonus attack with Autoblasters (granted by Stabilized S-foils).

[Ketsu & Old Teroch]

Yes, Old Teroch's (Fang Fighter) ability does not have requirements nor costs, and is able to freely enter the ability queue.

[Ciena Ree and Disciplined]

Yes, Ciena Ree (TIE Interceptor) may add both abilities to the queue, then resolve them in your desired order.

[Finch Dallow ability and Thermal Detonator template restriction]

Finch Dallow's (MG-100 StarFortress) ability is a replacement effect which allows you to replace either or both of a double Thermal Detonators drop.

-Yes, you may use Finch's ability on one of the Thermal Detonators.

-Yes, you may use Finch's ability on both.

-Yes, if you drop only 1 Thermal Detonator, you may use Finch's ability on it.

[Concussion bombs and replacement effect for dropping them]

Concussion Bomb's "must" forces you to spend a charge and drop the bomb using the 1-straight template.  As you do so, you may use replacement effect abilities to alter that 1 template drop.

[Automated Target priority and Targeting Synchronizer]

If the Jinata Security Officer (Scum Y-Wing) in this scenario chooses Ion Torpedo as the attack, it must declare enemy A as the defender, as it is the defender at the closest valid attack range.

[Does Plated Hull works only in the modify dice step or does it work all through the defending process?]

Yes, Plated Hull is a dice modification.  It takes place during step 2b. of Attack:

"Modify Attack Dice: The players resolve abilities that modify the attack dice. The defending player resolves their abilities first, then the attacking player resolves their abilities."

[Joph Seastriker pilot ability]

Yes, damage is suffered one at a time.  Each damage that causes Joph Seastriker (T-70 X-Wing) to lose a shield, triggers his ability.

[Autoblaster range3 for its bulleye]

My apologies!  I should have understood.

When attacking with Autoblasters, if the defender is in your bullseye arc, even if it is at range 3, you roll 1 additional die.

[Nantex tractoring itself and then using ensnare on opponent]

-You may not rotate and gain stress if the tractor effect was your own.  It must have been your opponent's.

-The post-tractor rotate is always 90° to the left or right, not 180°.

-I'm uncertain what this question is asking: "If the 90° rotation is done after a barrel roll slide, will it follow the barrel roll new position or the front/back pegs as usual?"

-Yes, Ensnare permits the Nantex to tractor another (small base) ship.  If this results in barrel rolling or boosting an opponent's ship, that ship may rotate 90° and gain a stress.

 

 

[Tel Trevura and Hull Upgrade]

Yes, if Tel Trevura (JumpMaster 5000) is equipped with Hull Upgrade, after using his ability, it would take 2 damage cards to destroy him.

[Dark Sidous coordination and linked actions]

Yes, both abilities enter the ability queue, and you may resolve them in your desired order.  You may:

-Perform purple coordinate to boost a V-Wing, which triggers both the V-Wing's linked action and Darth Sidious' ability
-Resolve the linked action (red lock)
-Resolve Sidious, which gives the V-Wing another stress token, then a focus token

[Autoblaster range3 for its bulleye]

Autoblasters' attack range is 1-2.  It is impossible to use it at range 3.

[Clarification for rotating after being tractored and moved by the opponent]

Interpretation a) is correct.  Whenever an opponent tractors you and causes you to barrel roll or boost, you may choose to rotate 90˚ and gain one stress token.  Whether or not you overlap an obstacle is irrelevant.

[Synced Laser Cannons, when is the ship no longer "Calculating"?]

Yes, in this scenario, the defending ship would apply the range 3 bonus.  The attacking ship no longer has a Calculate token, which is what defines "calculating".

[Boba Fett Rerolls question]

When Boba Fett (Scum, Firespray) uses his pilot ability, he must reroll all chosen dice simultaneously.