For my mod, I need some spare damage types for some of the interesting things I want.

But I have a few questions...
1. Do these (possibly unused) types have anything special about them: DEPLOY, SURRENDER, HACK, PENALTY, DISARM?
2. Do these (used) types have anything special about them: INFANTRY_MISSILE, AURORA_BOMB, LAND_MINE, JET_MISSILES, STEALTHJET_MISSILES, MOLOTOV_COCKTAIL, COMANCHE_VULCAN?
3. If a unit has armor with UNRESISTABLE 0%, can it still be killed by unresistable damage?
4. Where are WATER and FALLING used? They seem obvious, but I can't find specific references to them so I'm not sure if they are actually used.