Relic Castle

i can't playtest with my file. If i try and start it, it says this:

---------------------------
Pokemon Essentials
---------------------------
[Pokémon Essentials version 17]

Exception: RuntimeError

Message: filename is nil

SpriteWindow_sprites:30:in `initialize'

Pokemon_Sprites:223:in `new'

Pokemon_Sprites:223:in `pokemon='

Pokemon_Sprites:209:in `initialize'

PScreen_Load:165:in `new'

PScreen_Load:165:in `pbSetParty'

PScreen_Load:164:in `each'

PScreen_Load:164:in `pbSetParty'

PScreen_Load:319:in `pbStartLoadScreen'

Main:6:in `main'



This exception was logged in

C:\Users\larsh\Saved Games\Pokemon Essentials\errorlog.txt.

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Can anyone help me with this?