--- a/gwt-client/src/main/java/org/dive4elements/river/client/client/ui/DatacageTwinPanel.java	Mon Jul 22 11:07:14 2013 +0200
+++ b/gwt-client/src/main/java/org/dive4elements/river/client/client/ui/DatacageTwinPanel.java	Mon Jul 22 11:11:05 2013 +0200
@@ -393,6 +393,7 @@
         }
 
         // Clone new ones (and spawn statics), go forward.
+        parameterList.lockUI();
         loadArtifactService.loadMany(
             this.collection,
             toClone,
@@ -403,6 +404,7 @@
                 @Override
                 public void onFailure(Throwable caught) {
                     GWT.log("Failure of cloning with factories!");
+                    parameterList.unlockUI();
                 }
                 @Override
                 public void onSuccess(Artifact[] artifacts) {
@@ -411,6 +413,7 @@
 
                     fireStepForwardEvent(new StepForwardEvent(
                         getData(toClone, artifacts, toUse)));
+                    parameterList.unlockUI();
                 }
             });
     }