[Alphathon]

The immunity to damage types is set in armor.ini. You make an ArmorSet, like this:

Armor GateArmor
  Armor = CRUSH                     0%
  Armor = ARMOR_PIERCING     0%   
  Armor = INFANTRY_MISSILE    0%
  Armor = FLAME                       0%    
  Armor = PARTICLE_BEAM        0%   
  Armor = SNIPER                     0%
  Armor = LASER                       0%    
  Armor = HAZARD_CLEANUP     0%      
  Armor = KILL_PILOT               0%      
  Armor = SURRENDER              0% 
  Armor = SUBDUAL_MISSILE    0%
  Armor = SUBDUAL_VEHICLE    0%
  Armor = SUBDUAL_BUILDING  0%
  Armor = ...
  ...etc.
End

Then choose a damage type which you aren't going to use in you're mod, lets say Flame damage, and make it 100% or higher:

  Armor = INFANTRY_MISSILE    0%
  Armor = FLAME                       99999%    
  Armor = PARTICLE_BEAM        0%

In this case the armour makes the gate take a hell of a lot of damage from flame weapons (999.99 times the normal damage to be precise), but none form any other type.

Now to apply it simply look through the Gate code till you find something like this:

ArmorSet
  Conditions      = None
  Armor            = TankArmor
  DamageFX      = TankDamageFX
End

And make it read

ArmorSet
  Conditions      = None
  Armor            = GateArmor
  DamageFX      = None
End

Thats all there is to it.



Now, I have a question, is it possible to force a unit to gain an upgrade by shooting it or something, coz if there is I have a simpler way of doing this, as well as needing it for something I have planned in my own mod.