[Error] Pokedex Error

Hey there, this will be my first post as I've been content figuring things out for myself as I go, but for this I can't find any logical reason the error is reoccurring. This is what's happening:

---------------------------
Pokemon Essentials
---------------------------
[Pokémon Essentials version 17.2]

Exception: NoMethodError

Message: undefined method `[]' for nil:NilClass

PScreen_PokedexEntry:37:in `pbStartScene'

PScreen_PokedexEntry:562:in `pbStartScreen'

PScreen_PokedexMain:811:in `pbDexEntry'

PScreen_PokedexMain:1179:in `pbPokedex'

PScreen_PokedexMain:1155:in `loop'

PScreen_PokedexMain:1182:in `pbPokedex'

PScreen_PokedexMain:1154:in `pbActivateWindow'

PScreen_PokedexMain:1154:in `pbPokedex'

PScreen_PokedexMain:1196:in `pbStartScreen'

PScreen_PauseMenu:159:in `pbStartPokemonMenu'
===========================================

I haven't been able to see what exactly is causing it to happen. Any help is hugely appreciated!

I think it might be something to do with the new Region I'm trying to input, but I'm not entirely sure what:

DEXDEPENDSONLOCATION = false
def pbDexNames; return [
[_INTL("Kanto Pokédex"),0],
[_INTL("Johto Pokédex"),1],
[_INTL("Alyssia Pokédex"),2],
_INTL("National Pokédex")
]; end
ALWAYSSHOWALLFORMS = false
DEXINDEXOFFSETS = []

It all seems fine, here's an example entry that causes the error:

InternalName=BLASTOISEP
Type1=WATER
Type2=STEEL
BaseStats=99,83,120,58,65,105
GenderRate=Genderless
GrowthRate=Parabolic
BaseEXP=239
EffortPoints=4,0,6,0,0,0
Rareness=45
Happiness=70
Abilities=FLASHFIRE
HiddenAbility=FLAREBOOST
Moves=1,FLASHCANNON,1,METALCLAW,1,FIREFANG,1,WATERSPOUT,1,IRONDEFENSE,4,TAILWHIP,7,WATERGUN,10,IRONDEFENSE,13,EMBER,16,AQUARING,20,GYROBALL,24,SHIFTGEAR,28,SCALD,32,METALBURST,39,IRONHEAD,46,RAZORSHELL,53,RAINDANCE,60,HYDROPUMP,65,HEAVYSLAM,69,WATERSPOUT,74,METEORMASH
Compatibility=Undiscovered
StepsToHatch=10000
Height=1.6
Weight=135.5
Color=Red
Shape=6
Habitat=Cave
RegionalNumbers=1,1,9
Kind=Ruby Turtle
Pokedex=Steam pours from it's cannons at it walks. Bodies of water have been known to evaporate in seconds if it swims too long.
BattlerPlayerY=0
BattlerEnemyY=13
BattlerAltitude=0
Evolutions=

Google: https://reliccastle.com/threads/1967/

Thanks much! I came across this fix after posting this, aha.