I tried using the upgrader on a test instance copy and I see the same issue. This is the error message:
2015-10-12 11:41:34,490: [TP-Processor6] ERROR GrouperUiRestServlet.doGet(321) - - Problem calling reflection from URL: edu.internet2.middleware.grouper.grouperUi.serviceLogic
.UiV2Group.viewGroup
java.lang.RuntimeException: Problem converting JSP to string: /WEB-INF/grouperUi2/group/groupContents.jsp,
Problem calling method viewGroup on edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Group
at edu.internet2.middleware.grouper.ui.util.GrouperUiUtils.convertJspToString(GrouperUiUtils.java:1656)
at edu.internet2.middleware.grouper.grouperUi.beans.json.GuiScreenAction.newInnerHtmlFromJsp(GuiScreenAction.java:559)
at edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Group.filterHelper(UiV2Group.java:467)
at edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Group.viewGroup(UiV2Group.java:185)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:622)
at edu.internet2.middleware.grouper.util.GrouperUtil.invokeMethod(GrouperUtil.java:4002)
at edu.internet2.middleware.grouper.util.GrouperUtil.callMethod(GrouperUtil.java:3953)
at edu.internet2.middleware.grouper.j2ee.GrouperUiRestServlet.doGet(GrouperUiRestServlet.java:288)
at edu.internet2.middleware.grouper.j2ee.GrouperUiRestServlet.doPost(GrouperUiRestServlet.java:160)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
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.owasp.csrfguard.CsrfGuardFilter.doFilter(CsrfGuardFilter.java:110)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at edu.internet2.middleware.grouper.ui.GrouperUiFilter.doFilter(GrouperUiFilter.java:1015)
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:558)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:190)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:291)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:769)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:698)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:891)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:690)
at java.lang.Thread.run(Thread.java:701)
Caused by: org.apache.jasper.JasperException: javax.el.ELException: Error reading 'shortLinkWithIcon' on type edu.internet2.middleware.grouper.grouperUi.beans.api.GuiSubject
at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:491)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
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.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:551)
at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:488)
at edu.internet2.middleware.grouper.ui.util.GrouperUiUtils.convertJspToString(GrouperUiUtils.java:1654)
... 35 more
Caused by: javax.el.ELException: Error reading 'shortLinkWithIcon' on type edu.internet2.middleware.grouper.grouperUi.beans.api.GuiSubject
at javax.el.BeanELResolver.getValue(BeanELResolver.java:66)
at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
at org.apache.el.parser.AstValue.getValue(AstValue.java:118)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935)
at org.apache.jsp.WEB_002dINF.grouperUi2.group.groupContents_jsp._jspx_meth_c_005fforEach_005f0(groupContents_jsp.java:265)
at org.apache.jsp.WEB_002dINF.grouperUi2.group.groupContents_jsp._jspService(groupContents_jsp.java:125)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
... 44 more
Caused by: java.lang.NullPointerException
at edu.internet2.middleware.subject.provider.LdapSubject.getDescription(LdapSubject.java:146)
at edu.internet2.middleware.grouper.ui.util.GrouperUiUtils.convertSubjectToLabelConfigured(GrouperUiUtils.java:1359)
at edu.internet2.middleware.grouper.ui.util.GrouperUiUtils.convertSubjectToLabelLong(GrouperUiUtils.java:1009)
at edu.internet2.middleware.grouper.grouperUi.beans.api.GuiSubject.initScreenLabels(GuiSubject.java:225)
at edu.internet2.middleware.grouper.grouperUi.beans.api.GuiSubject.getShortLinkWithIcon(GuiSubject.java:200)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:622)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:62)
... 53 more
Also, FYI, the upgrader copied over the version of ojdbc6_g.jar that I need for our Oracle database, which caused database access to fail until I replaced it.