Game error

[bulba99]

When I try to load my save file I can't get past the menu screen and it gives me an error message. It reads "Script "PokemonField" line 1637: NoMethodError occured. undefined method "spriteset" for #<Scene_Intro:0xc7e7b88>". I played this game just 2 days before and it was running great. I left off training Pokemon in that area you meet spirit Keta and he wants to battle you. Only thing I can think of that is weird is I had 2 shadow pokemon on my team that I was training and I had mods on, but they were downloaded from here and was made by someone who I think it said helped make the game (could be wrong). I have redownloaded the game and restarted my computer, but I still get this message. My game closes if I x out of the message or click ok. Please help I would love to play the game again!