Yesterday a plugin user called me. One of his application users had this error dialog:
It looks like a typical cache trouble error, but in this case it was a virus scanner which put our DLLs into a quarantine so the application was not allowed to load them. In this case the ChartDirector plugin was not loaded so REALbasic failed to find the constructor (_init) for the CDPlotAreaMBS class.
This was fixed today with changing the virus scanner settings.