Does the use of a gunner major action always preclude the use of the Snap Shot minor crew action?

In Starfinder, during starship combat, the Snap Shot minor crew action allows a crew member who has taken a major crew action earlier in the round to fire a starship weapon during the gunnery phase. The rules state:

You can fire one of your starship’s weapons with a –2 penalty to the gunnery check. You can take this action only if no other gunner actions have been taken during the gunnery phase (including snap shot).

The wording of the second sentence raises questions. Does it disallow Snap Shot actions completely if another character intends to take a gunner major action? Does it disallow Snap Shot actions unless they’re taken before all gunner major actions for the round? Or does it simply disallow Snap Shot if the character attempting it has already carried out a gunner major action?

The scenario I am facing in play is this: a pilot has completed a pilot major action in the Helm phase and positioned the ship to put the enemy ship in the port quadrant. There are two gunners on board. The first gunner has fired at the enemy ship with a turreted weapon. The second gunner has fired at the enemy ship with a port arc weapon. The pilot’s player points out that the ship also has a forward arc weapon that has the broad arc property–meaning that it can target ships in the port or starboard arcs with a -2 penalty. He wishes to Snap Shoot the broad arc weapon at the ship in the port arc with a cumulative penalty of -4 (-2 for firing outside the weapon’s normal arc and -2 for the fact that it is a Snap Shot). This seems like a reasonable request to me, but do the rules preclude it? If they do, then had the pilot declared this intention before the other gunners rolled, would he have been able to do it within the rules?

How does the reaction from rank I of the Heavy Gunner talent, Covering Fire, work with area-of-effect attacks?

Rank I of the Heavy Gunner talent, Covering Fire, is described on page 97 of the Lancer Core Book First Edition PDF as follows (emphasis mine):

As a quick action, choose a character within line of sight and RANGE of one of your HEAVY ranged weapons, and within 10 spaces: they are Impaired until the start of your next turn. For the duration, if your target moves more than 1 space, they clear Impaired, but you may attack them as a reaction with a HEAVY ranged weapon for half damage, [Heat], or [Burn], and then this effect ends. You can make this attack at any point during their movement (e.g., waiting until they exit cover).

COVERING FIRE can only affect one character at a time – subsequent uses replace previous ones – and it immediately ends if your target damages you.

As p. 104 of the core book notes below the “Patterns” subheading in the “Weapon Tags” section, some weapons affect an area rather than a single target:

Some weapons and systems have special attack patterns: LINE, CONE, BLAST, and BURST. These attacks affect all targets within a defined area and require a separate attack roll for each target. Damage is only rolled once, and bonus damage is halved if there are multiple targets affected.

The section then describes how those 4 kinds of AoEs work in particular.

How does Covering Fire’s reaction work with area-of-effect attacks?

  • To begin with, can AoE attacks (with heavy ranged weapons) even be made using the reaction from Covering Fire?
  • If so, do they need to be centered (or otherwise focused) on the character chosen for Covering Fire? Or can they be placed in any configuration as long as the chosen character is in the AoE? (Does the answer differ based on which AoE pattern the attack has to use?)
  • Does the reaction attack only affect the chosen character? Or does it affect other targets in the AoE as it would otherwise? (If it does affect other targets in the AoE, do they take full damage/Heat/Burn, or is it also halved?)