RulesListener exceptin raised after fixing the px number of banner image of home page for its position from top and left

Defined a px number for the top and left position of banner image of home page (in web template) in update pop up engine of banner.image , putting 10 in the fields 'position from top' and 'Position form left' and cllicked on apply button , the result in the console:
008-12-22 14:09:52,531: ERROR [org.jahia.services.content.automation.RulesListener] - Error when executing event
avax.jcr.PathNotFoundException: cast
at org.jahia.services.content.impl.jahia.NodeImpl.getProperty(NodeImpl.java:246)
at org.jahia.services.content.impl.jahia.SessionImpl.getItem(SessionImpl.java:159)
at org.jahia.services.content.automation.RulesListener.onEvent(RulesListener.java:217)
at org.jahia.services.content.impl.jahia.ObservationManagerImpl.callListeners(ObservationManagerImpl.java:228)
at org.jahia.services.content.impl.jahia.ObservationManagerImpl.fire(ObservationManagerImpl.java:168)
at org.jahia.services.content.impl.jahia.ObservationManagerImpl.fireEvents(ObservationManagerImpl.java:70)
at org.jahia.services.content.impl.jahia.JCRListener.aggregatedObjectChanged(JCRListener.java:43)
at sun.reflect.GeneratedMethodAccessor698.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jahia.registries.JahiaListenersRegistry.wakeupListeners(JahiaListenersRegistry.java:173)
at org.jahia.services.events.JahiaEventGeneratorBaseService.fireAggregatedEvents(JahiaEventGeneratorBaseService.java:121)
at org.jahia.services.events.JahiaEventGeneratorBaseService$$FastClassByCGLIB$$15089916.invoke(<generated>)
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:700)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.aop.interceptor.AbstractTraceInterceptor.invoke(AbstractTraceInterceptor.java:113)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:635)
at org.jahia.services.events.JahiaEventGeneratorBaseService$$EnhancerByCGLIB$$4cf7d7fb.fireAggregatedEvents(<generated>)
at org.jahia.operations.valves.EngineValve.processEngineRequest(EngineValve.java:211)
at org.jahia.operations.valves.EngineValve.invoke(EngineValve.java:79)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.PlutoProcessActionValve.invoke(PlutoProcessActionValve.java:166)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.SkeletonAggregatorValve.invoke(SkeletonAggregatorValve.java:77)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.ThemeValve.invoke(ThemeValve.java:76)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.UserAgentViewSwitcherValve.invoke(UserAgentViewSwitcherValve.java:42)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.HistoryValve.invoke(HistoryValve.java:31)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.PageAccessCheckValve.invoke(PageAccessCheckValve.java:73)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.OperationModeCheckValve.invoke(OperationModeCheckValve.java:84)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.operations.valves.SiteCheckValve.invoke(SiteCheckValve.java:78)
at org.jahia.pipelines.impl.GenericPipeline.invokeNext(GenericPipeline.java:163)
at org.jahia.pipelines.impl.GenericPipeline.invoke(GenericPipeline.java:150)
at org.jahia.operations.OperationManager.handleOperations(OperationManager.java:81)
at org.jahia.bin.JahiaAction.execute(JahiaAction.java:74)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
at org.jahia.bin.JahiaRequestProcessor.process(JahiaRequestProcessor.java:82)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.jahia.bin.Jahia.process(Jahia.java:1557)
at org.jahia.bin.Jahia.service(Jahia.java:851)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.jahia.bin.filters.jcr.JcrSessionFilter.doFilter(JcrSessionFilter.java:23)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.tuckey.web.filters.urlrewrite.RuleChain.handleRewrite(RuleChain.java:164)
at org.tuckey.web.filters.urlrewrite.RuleChain.doRules(RuleChain.java:141)
at org.tuckey.web.filters.urlrewrite.UrlRewriter.processRequest(UrlRewriter.java:90)
at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:417)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.jahia.bin.filters.ResponseCacheControlFilter.doFilter(ResponseCacheControlFilter.java:94)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:568)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:595)