Schedule a group operation for execution in the future. Make sure you tell it to execute in a specific order of resources (i.e. not parallel).

Once scheduled, go view the schedule's details. Then hover over the resources in the resource list. Notice you get a red globally caught exception message:

com_google_gwt_lang_Cast_dynamicCast__Ljava_lang_Object_2ILjava_lang_Object_2((com_smartgwt_client_util_JSOHelper_getAttributeAsObject__Lcom_google_gwt_core_client_JavaScriptObject_2Ljava_lang_String_2Ljava_lang_Object_2_ret_0 = listGridRecord.com_smartgwt_client_core_JsObject_jsObj[$intern_3121], com_smartgwt_client_util_JSOHelper_getAttributeAsObject__Lcom_google_gwt_core_client_JavaScriptObject_2Ljava_lang_String_2Ljava_lang_Object_2_ret_0 === undefined ? null : com_smartgwt_client_util_JSOHelper_getAttributeAsObject__Lcom_google_gwt_core_client_JavaScriptObject_2Ljava_lang_String_2Ljava_lang_Object_2_ret_0), 628) is null stack: org_rhq_enterprise_gui_coregui_client_inventory_resource_AncestryUtil_getAncestryHoverHTML__Lcom_smartgwt_client_widgets_grid_ListGridRecord_2ILjava_lang_String_2([object Object],0)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html:62233 org_rhq_enterprise_gui_coregui_client_inventory_groups_detail_operation_schedule_GroupOperationScheduleDetailsView$2_hoverHTML__Ljava_lang_Object_2Lcom_smartgwt_client_widgets_grid_ListGridRecord_2IILjava_lang_String_2("RHQ Agent",[object Object],2,1)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html:61601 ([object Object],"RHQ Agent",2,1,[object Object])@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html:23522 com_google_gwt_core_client_impl_Impl_entry0__Ljava_lang_Object_2Ljava_lang_Object_2Ljava_lang_Object_2Ljava_lang_Object_2((function (record, value, rowNum, colNum, grid) {var recordJ = com_smartgwt_client_widgets_grid_ListGridRecord_getOrCreateRef__Lcom_google_gwt_core_client_JavaScriptObject_2Lcom_smartgwt_client_widgets_grid_ListGridRecord_2(record);var valueJ = $wnd.SmartGWT.convertToJavaType(value);return hoverCustomizer.hoverHTML__Ljava_lang_Object_2Lcom_smartgwt_client_widgets_grid_ListGridRecord_2IILjava_lang_String_2(valueJ, recordJ, rowNum, colNum);}),[object Object],[object Object])@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html:2474 ([object Object],"RHQ Agent",2,1,[object Object])@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html:2461 isc_ListGrid_cellHoverHTML([object Object],2,1)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Grids.js:1557 anonymous([object Object],2,1)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Grids.js:927 isc_GridRenderer__showHover([object Object],2,1)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Grids.js:718 isc_GridRenderer__cellHover(2,1)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Grids.js:717 isc_c_Hover__doAction()@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Core.js:3764 isc_c_Class_fireCallback([object Object],(void 0),[object Array],[object Object],true)@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Core.js:296 isc_c_Timer__fireTimeout("$ir9400")@http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Core.js:1186 @http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/sc/modules/ISC_Core.js:1181 fileName: http://localhost:7080/coregui/org.rhq.enterprise.gui.coregui.CoreGUI/8E219719088408D1097A8BE5443CBF2D.cache.html lineNumber: 62233
    at Unknown.org_rhq_enterprise_gui_coregui_client_inventory_resource_AncestryUtil_getAncestryHoverHTML__Lcom_smartgwt_client_widgets_grid_ListGridRecord_2ILjava_lang_String_2(Unknown source:0)
    at Unknown.org_rhq_enterprise_gui_coregui_client_inventory_groups_detail_operation_schedule_GroupOperationScheduleDetailsView$2_hoverHTML__Ljava_lang_Object_2Lcom_smartgwt_client_widgets_grid_ListGridRecord_2IILjava_lang_String_2(Unknown source:0)
    at Unknown.anonymous(Unknown source:0)
    at Unknown.com_google_gwt_core_client_impl_Impl_entry0__Ljava_lang_Object_2Ljava_lang_Object_2Ljava_lang_Object_2Ljava_lang_Object_2(Unknown source:0)
    at Unknown.anonymous(Unknown source:0)
    at Unknown.isc_ListGrid_cellHoverHTML(Unknown source:0)
    at Unknown.anonymous(Unknown source:0)
    at Unknown.isc_GridRenderer__showHover(Unknown source:0)
    at Unknown.isc_GridRenderer__cellHover(Unknown source:0)
    at Unknown.isc_c_Hover__doAction(Unknown source:0)
    at Unknown.isc_c_Class_fireCallback(Unknown source:0)
    at Unknown.isc_c_Timer__fireTimeout(Unknown source:0)
    at Unknown.anonymous(Unknown source:0)
    at Unknown.anonymous(Unknown source:0)