[Error] Using items in battle not working

[A30502355]

I don't know how. But whenever I use a healing item or just about any item on ANY pokémon that's not the one in the lead, it will not work. No error messages, it just goes straight to the opponent's turn. Even when I switch the lead pokémon out, only the one that was ORIGINALLY in the lead at the start of the battle can items be used on. Oddly enough, the X-items work fine, just items you can use on a pokémon in the back, so just about every other item.
I don't know if an external thing I might have edited caused this, but this is what I believe to be the culprit, problem is, I can't find a solution (In PokeBattle_Battle):

################################################################################
# Using an item.
################################################################################
# Uses an item on a Pokémon in the player's party.
  def pbUseItemOnPokemon(item,pkmnIndex,userPkmn,scene)
    pokemon=@party1[pkmnIndex]
    battler=nil
    name=pbGetOwner(userPkmn.index).fullname
    name=pbGetOwner(userPkmn.index).name if pbBelongsToPlayer?(userPkmn.index)
    pbDisplayBrief(_INTL("{1} used the\r\n{2}.",name,PBItems.getName(item)))
    PBDebug.log("[Use item] Player used #{PBItems.getName(item)} on #{pokemon.name}")
    ret=false
    if pokemon.isEgg?
      pbDisplay(_INTL("But it had no effect!"))
    else
      for i in 0...4
        if !pbIsOpposing?(i) && @battlers[i].pokemonIndex==pkmnIndex
          battler=@battlers[i]
        end
      end
      ret=ItemHandlers.triggerBattleUseOnPokemon(item,pokemon,battler,scene)
    end
    if !ret && pbBelongsToPlayer?(userPkmn.index)
      if $PokemonBag.pbCanStore?(item)
        $PokemonBag.pbStoreItem(item)
      else
        raise _INTL("Couldn't return unused item to Bag somehow.")
      end
    end
    return ret
  end

# Uses an item on an active Pokémon.
  def pbUseItemOnBattler(item,index,userPkmn,scene)
    PBDebug.log("[Use item] Player used #{PBItems.getName(item)} on #{@battlers[index].pbThis(true)}")
    ret=ItemHandlers.triggerBattleUseOnBattler(item,@battlers[index],scene)
    if !ret && pbBelongsToPlayer?(userPkmn.index)
      if $PokemonBag.pbCanStore?(item)
        $PokemonBag.pbStoreItem(item)
      else
        raise _INTL("Couldn't return unused item to Bag somehow.")
      end
    end
    return ret
  end

  def pbRegisterItem(idxPokemon,idxItem,idxTarget=nil)
    if idxTarget==0 && @battlers[idxTarget].effects[PBEffects::Embargo]>0
      pbDisplay(_INTL("Embargo's effect prevents the item's use on {1}!",@battlers[idxTarget].pbThis(true)))
      return false
    end
    if ItemHandlers.hasUseInBattle(idxItem)
      if idxPokemon==0 # Player's first Pokémon
        if ItemHandlers.triggerBattleUseOnBattler(idxItem,@battlers[idxPokemon],self)
          ItemHandlers.triggerUseInBattle(idxItem,@battlers[idxPokemon],self)
          if @doublebattle
            @choices[idxPokemon+2][0]=3         # "Use an item"
            @choices[idxPokemon+2][1]=idxItem   # ID of item to be used
            @choices[idxPokemon+2][2]=idxTarget # Index of Pokémon to use item on
          end
        else
          if $PokemonBag.pbCanStore?(idxItem)
            $PokemonBag.pbStoreItem(idxItem)
          else
            raise _INTL("Couldn't return unusable item to Bag somehow.")
          end
          return false
        end
      else
        if ItemHandlers.triggerBattleUseOnBattler(idxItem,@battlers[idxPokemon],self)
          pbDisplay(_INTL("It's impossible to aim without being focused!"))
        end
        return false
      end
    end
    @choices[idxPokemon][0]=3         # "Use an item"
    @choices[idxPokemon][1]=idxItem   # ID of item to be used
    @choices[idxPokemon][2]=idxTarget # Index of Pokémon to use item on
    side=(pbIsOpposing?(idxPokemon)) ? 1 : 0
    owner=pbGetOwnerIndex(idxPokemon)
    if @megaEvolution[side][owner]==idxPokemon
      @megaEvolution[side][owner]=-1
    end
    return true
  end

  def pbEnemyUseItem(item,battler)
    return 0 if !@internalbattle
    items=pbGetOwnerItems(battler.index)
    return if !items
    opponent=pbGetOwner(battler.index)
    for i in 0...items.length
      if items[i]==item
        items.delete_at(i)
        break
      end
    end
    itemname=PBItems.getName(item)
    pbDisplayBrief(_INTL("{1} used the\r\n{2}!",opponent.fullname,itemname))
    PBDebug.log("[Use item] Opponent used #{itemname} on #{battler.pbThis(true)}")
    if isConst?(item,PBItems,:POTION)
      battler.pbRecoverHP(20,true)
      pbDisplay(_INTL("{1}'s HP was restored.",battler.pbThis))
    elsif isConst?(item,PBItems,:SUPERPOTION)
      battler.pbRecoverHP(50,true)
      pbDisplay(_INTL("{1}'s HP was restored.",battler.pbThis))
    elsif isConst?(item,PBItems,:HYPERPOTION)
      battler.pbRecoverHP(200,true)
      pbDisplay(_INTL("{1}'s HP was restored.",battler.pbThis))
    elsif isConst?(item,PBItems,:MAXPOTION)
      battler.pbRecoverHP(battler.totalhp-battler.hp,true)
      pbDisplay(_INTL("{1}'s HP was restored.",battler.pbThis))
    elsif isConst?(item,PBItems,:FULLRESTORE)
      fullhp=(battler.hp==battler.totalhp)
      battler.pbRecoverHP(battler.totalhp-battler.hp,true)
      battler.status=0; battler.statusCount=0
      battler.effects[PBEffects::Confusion]=0
      if fullhp
        pbDisplay(_INTL("{1} became healthy!",battler.pbThis))
      else
        pbDisplay(_INTL("{1}'s HP was restored.",battler.pbThis))
      end
    elsif isConst?(item,PBItems,:FULLHEAL)
      battler.status=0; battler.statusCount=0
      battler.effects[PBEffects::Confusion]=0
      pbDisplay(_INTL("{1} became healthy!",battler.pbThis))
    elsif isConst?(item,PBItems,:XATTACK)
      if battler.pbCanIncreaseStatStage?(PBStats::ATTACK,battler)
        battler.pbIncreaseStat(PBStats::ATTACK,1,battler,true)
      end
    elsif isConst?(item,PBItems,:XDEFEND)
      if battler.pbCanIncreaseStatStage?(PBStats::DEFENSE,battler)
        battler.pbIncreaseStat(PBStats::DEFENSE,1,battler,true)
      end
    elsif isConst?(item,PBItems,:XSPEED)
      if battler.pbCanIncreaseStatStage?(PBStats::SPEED,battler)
        battler.pbIncreaseStat(PBStats::SPEED,1,battler,true)
      end
    elsif isConst?(item,PBItems,:XSPECIAL)
      if battler.pbCanIncreaseStatStage?(PBStats::SPATK,battler)
        battler.pbIncreaseStat(PBStats::SPATK,1,battler,true)
      end
    elsif isConst?(item,PBItems,:XSPDEF)
      if battler.pbCanIncreaseStatStage?(PBStats::SPDEF,battler)
        battler.pbIncreaseStat(PBStats::SPDEF,1,battler,true)
      end
    elsif isConst?(item,PBItems,:XACCURACY)
      if battler.pbCanIncreaseStatStage?(PBStats::ACCURACY,battler)
        battler.pbIncreaseStat(PBStats::ACCURACY,1,battler,true)
      end
    end
  end

 

[A30502355]

Well to try to give more details I really REALLY want this fixed, please help me:
-I can still select the item to use on the pokemon originally in the 2nd - 6th slot. And it still consumes the item. But it just goes straight to the opponent's turn, no text, no error messages.
-Probably the reason why X items still work is because it didn't have to bring up the party menu to use it on perhaps?
-In double battles the same thing happens, only the mon in the first slot originally in the match does it work.

 

[A30502355]

Never mind, I figured it out on my own, just needed to change index == 0 to index >= 0