The value cannot be NaN error annoys the hell out of me

I was using a save file, and I was making a game, and when it was almost, nearly, completely done, or I press finish, this error pops up. After that error, I decided to restart and go back to the save, and it worked once. Then after a few games, the popup came again. I relaunched it, go back to my save, the popup came back. I did it again, and the error alert came up again. It’s like it wants to fuck up my save.

I had like lots of mods enabled, including the cheat mod, and excluding the Greenheart One (that replaces the GDT Mod API). What should I do to get the error off just so the popup would be gone more than once?

if you used UltimateLib then there’s your answer.

Well, I was using it,

Yeah, it can mess up a save really bad.