beta.curriki --> Go to Currikulum Builder-->click Edit link of a collection. Error message is shown.

beta.curriki -> Go to Currikulum Builder->click Edit link of a collection. The following Error message is shown.

curriki error -1
Error number -1 in 19: Asset does not allow derivatives com.xpn.xwiki.XWikiException: Error number -1 in 19: Asset does not allow derivatives at org.curriki.gwt.server.CurrikiServiceImpl.duplicateTemplateAsset(CurrikiServiceImpl.java:1050) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:281) at com.google.gwt.user.server.rpc.RemoteServiceServlet.doPost(RemoteServiceServlet.java:167) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:397) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:184) at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:216) at org.apache.catalina.core.ApplicationFilterChain.doFilter