Crates

Crate bonuses (by DCoder)

Crate functionality is described by two sections - CrateRules and Powerups. To each it's turn:

[CrateRules] - this section covers generic stuff, like how often to spawn crates, how many of them to spawn, etc. It has lots of comments, so every tag should be self-explanatory.
CrateMaximum=255 ; crates can never exceed this quantity
CrateMinimum=1 ; crates are normally one per human player but never below this number
CrateRadius=3.0 ; radius (cells) for area effect crate powerup bonuses
CrateRegen=3 ; average minutes between random powerup crate regeneration
SilverCrate=HealBase ; solo play silver crate bonus
SoloCrateMoney=5000 ; money to give for money crate in solo play missions
UnitCrateType=none ; specifies specific unit type for unit type crate ['none' means pick randomly]
WoodCrate=Money ; solo play wood crate bonus
WaterCrate=Money; solo play water crate bonus
HealCrateSound=HealCrate; heal crate sound effect
WoodCrateImg=CRATE ; wood crate overlay image to use
CrateImg=CRATE ; normal crate overlay image to use
WaterCrateImg=WCRATE; Water crate image
FreeMCV=yes ; Give free MCV from crate if no buildings but still has money [multiplay only]?

What you get out of a crate is dictated by the [Powerups] section.

[Powerups]
Armor=10,ARMOR,yes,1.5 ;Unit's Strength= is multiplied by the param#4
Firepower=10,FIREPOWR,yes,2.0 ;Unit Weapons' Damage= is multiplied by the param#4
HealBase=10,HEALALL,yes ;All the player's stuff goes to 100% health
Money=20,MONEY,yes,2000 ;Random amount of cash(max amount = param#4)
Reveal=10,REVEAL,yes ;All map is revealed
Speed=10,SPEED,yes,1.2 ;Unit's Speed= is multiplied by the param#4
Veteran=20,VETERAN,yes,1 ;Unit is promoted(through as many levels as param#4 says)
Unit=20,<none>,no ;Random unit is given¹
Invulnerability=0,ARMOR,yes,1.0 ;Nothing happens²
IonStorm=0,<none>,yes ;Nothing happens²
Gas=0,<none>,yes,100 ;Unknown effect
Tiberium=0,<none>,no ;A random patch of Ore is created at the cell
Pod=0,<none>,no ;Nothing happens²
Cloak=0,CLOAK,yes ;Unit is cloaked (like the Stealth Tank/Submarine)
Darkness=0,SHROUDX,yes ;Map is reshrouded
Explosion=0,<none>,yes,500 ;An explosion deals param#4 of damage, warhead unknown
ICBM=0,CHEMISLE,yes ;A ready one-shot Nuke is given if you don't have it
Napalm=0,<none>,no,600 ;An fire explosion deals param#4 of damage, Warhead=Fire
Squad=0,<none>,no ;Nothing happens²

The first parameter dictates the chance of getting this kind of crate. It does not mean %, it means 'param#1 shares out of all possible shares'.
The second one says what animation to play.
Third one says if this crate can be found on water.
The fourth one varies by crate.

¹ [CrateRules]
UnitCrateType=none ; specifies unit type for unit type crate ['none' means pick randomly] If this is set to 'none, that means a random unit is picked randomly form an array of units without CrateGoodie=no.

Problem is that certain naval units are also CrateGoodie=yes or lack CrateGoodie=no. The game does not differentiate between naval and ground vehicles, and might give you a naval unit on a no-water map, resulting in an Internal Error. If the map does contain water, though, the naval unit will be spawned in the water without the error. So best to set all naval units to CrateGoodie=no (note, originally the Destroyer lacks this tag, so fix it too).

² The animation is played anyway, and since you can attach a Damage= to an animation as well as MakeInfantry=, you can get all kinds of effects from that...