There is a bug in the JFCRipperMointor in JFCRipper project. This function calls the target program like this: application.connect(); which means it is not passing any arguments.
If you change this line to:
String [] args = configuration.ARGUMENT_LIST.split(";");
application.connect(args);
and recompile, build, dist this project and run GanttProject (input project) you should get past this error.
Thanks for reporting this bug. We will update this fix in the next release.