Does anyone know how to fix this error in Gravemind 1.5? It happens whenever I open a campaign file:

"The output char buffer is too small to contain the decoded characters, encoding 'Unicode (UFT-8)'fallback
'System.Text.DecoderReplacementFallback'.
Parameter name: chars."

Am I doing something wrong? I'm not the most hardcore modder so I'd be grateful for any help.