"The png item could not be loaded from the resource ID."

I added the Gibraltar leagues from Steam and every time I exit FM and open Genie Scout I see about 50 pop-up messages saying: "The png item could not be loaded from the resource ID". Everything else works fine but the error messages can be irritating. Does anyone know how to fix this problem?

I'm getting this same problem. It's a real pain. Is it because of custom leagues?