EDIT: Annatar11 beat me to it! He's good, real good at that.

WeaponType- this refers to a generic setting; there are three different settings- Projectile (Plasma, Autocannon, Laser, Wave, Pulse Gun), Missile (Missile, Phase Missile), and Beam (Beam, Pulse Beam).

Attack Type refers to the attack type of a weapon; this determines its % bonus against different armor types.

Damage Type refers to how damage is applied in reference to the particle effects. BACKLOADED means that when the last weapon effect hits the target, damage is applied. OVERTIME works, well over the duration of the effects. OVERTIME will work with projectile weapons (like the aforementioned list and Missile weapons). In vanilla, it is only used on Beam weapons (Beam, Pulse Beam).

WeaponClassType refers to the weapon class. These are some: FLASHBEAM (Pulse Beam), AUTOCANNON (Autocannon).

DamagePerBank refers to the amount of damage in a particular direction.

Synchronized Targeting. Hmm. I'm not really sure what this one does, though my guess is that a particular weapon type uses a synchronized targeting scheme (basically FFs that weapon type).

PointStaggerDelay I believe refers to the particle effects. I'm not sure though, as it could also refer to the damage point staggering.

As for XSI-relation, this is what is needed- A ship can only have three weapon types on it. Weapon-0, Weapon-1, and Weapon-2 (for XSI). Abilities (in Entrenchment) can go up to five, four active&1 passive (Ability-0 thru -4). You can have a maximum of 60 weapon hardpoints, and 10 of any other. However, the 60 weapon points are shared between three types (the equality of it is dependent on the model), while ability hardpoints  can actually be as many as 40, with 10 for each ability (50 in Entrenchment).

You do not differentiate banks in XSI. It is unneeded. In all reality, I gather that you pulled these lines out of a ship entity file. None of the entity file settings actually relate to the mesh except for the lines that delineate the shieldmesh name and the mesh info. Weapon delineation is done by naming the hardpoints 'Weapon-0' for your 1st weapon, 'Weapon-1' for the 2nd, and 'Weapon-2' for the 3rd.

I haven't seen a lit of the WeaponClassTypes, however there's a very finite amount. Look through all the capital ships of each race, and you should get most of them

There's no way to make a new one, but again as far as the game is concerned there is no difference in mechanics between Physical and Energy damage. The only thing that actually looks at it is the one ability setting that can modify the cooldown of Energy weapons. But that's it.

SynchronizedTargeting does not effect when the weapon points fire relative to each other - that would be a PointStaggerDelay of 0. Rather, it causes all weapon effects to converge to the same point on the target rather than hitting different areas on the ship.

Also at least BurstCount does change average DPS of the weapon, if not PointStaggerDelay.

can you tell me more about these? anything really whats the diff is there a diff effect? do you still have the mod?

well, actually, planet-bombing damage is just given as 'bombing damage' under infocards.

The only thing weapon classes are used for to my knowledge is to delineate different weapon researches, and also add some variety, as well as different strings values.

The ION weapon type I haven't a clue as to what it may have been the basis of. PLANETBOMBARDMENT may have been the basis of TEC bombing gear, and DART may have been the basis of Advent bombing gear.

While I do still have the mod, I was adding stuff to it that caused issues to stability, so I zipped it up to a different directory on my computer to fix it back to normal.

As for uploading it, NO. The mod was mostly just testing out a lot of stuff. I am working on a mod, but you won't likely see it for a while. At least not until after the beta release of Halo: Sins of the Prophets.

The Weapon Class Type names are defined in the Strings file. Just use the search function in WordPad to find the 'ION' line. Make sure that you check 'Whole Word Only' and 'Case Sensitive'.