This is a normal error and is caused by the Quint ray tracing shader not being included by default in the texture pack since it’s exclusive to Marty McFly Patrons (I can’t distribute it). The error happens because it can’t find the shader itself, but there is a configuration file for it if it would have found it. ReShade thinks something’s wrong, but everything’s working as expected! So you can just ignore the error. In future releases the message will be removed to avoid confusion. I hope this answers your question!