Let's build a Patrol Corvette:
Weapons:
Specify two triple laser turrets:
Each turret consumes 13 Power = 1 for the turret + 3 × 4 Power for the lasers.
Weapon System Summary only uses one mount, not all two.
Bottom pane has the same problem.
Only one Dton is added to the ship for two turrets.
Mount Quantity: Max is three mounts on a ship with four hardpoints.
Gunners Required is one per turret, so two gunners, not 1.
Firmpoints Used should be "0 / 0", not "2 / 0".
Add two triple missile turrets:
Weapon Systems Summary only recognises one turret of each type, except hardpoint summary is correct.
Missile turrets require one Power each, for the turret.
Missile turrets don't combine damage, missiles are launched in salvoes doing individual damage.
Each turret requires one gunner.