Those weapons are all fired from the same set of controls, so it would be akin to firing off a paired set of identical weapons:
...an Operator can use its Action to control one (and only one) System on a Creation, against a single target...
...Ranged Weapons: firing a single weapon, or a paired set of identical weapons, at a single target...
I'm pretty sure you brought this up in another thread about CP cost as well, so I'll just go through the whole process, creation through firing.
To create the weapons you would have to pay for each one separately. For easiness, let's just say now that they are the weapons from an X-Wing (so four lazers) and each one is a 2d6 damage. You would pay for each one separately, the cost of FOUR 2d6 weapons.
When you are firing all of these, you press only one button and they all fire simultaneously (for sake of argument. They actually fire in a pattern, but in Brikwars it would be considered all at once) and you don't have to press an individual button for each. This pushing of ONE button is one action, as it fires one TYPE of weapon all connected to the same controls. You would not be able to fire these lazers and THEN fire a proton torpedo, as they are two different sets of controls and two different weapons.
You are only able to attack one target with all four of these shots and all of them must be able to hit (not blocked by anything and all within range). When you roll, you roll the Use Rating for EACH of the lazers, so you would have to roll 4 Skill Rolls at once. However many you make hit. If you succeed on 3 out of the 4, you have hit with THREE of the lazers and would deal 2d6 times 3, or 6d6 damage.
The missed shots do have a chance of hitting another target. Just treat any missed shots as a regular Missed Shot and deal with it accordingly.