Replace that line with?
?self.panel = jmri.InstanceManager.getDefault(jmri.ConfigureManager).findInstance(java.lang.Class.forName("jmri.jmrit.display.layoutEditor.LayoutEditor"),0)
?
making sure to keep the same indentation. ?The change is from "configureManagerInstance()" to "getDefault(jmri.ConfigureManager)"
Bob