Index: lams_common/src/java/org/lamsfoundation/lams/learningdesign/ChosenGrouper.java
===================================================================
diff -u -r5009e72ce26a04aa0654d6a6a53eb177c99f42d8 -r7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f
--- lams_common/src/java/org/lamsfoundation/lams/learningdesign/ChosenGrouper.java	(.../ChosenGrouper.java)	(revision 5009e72ce26a04aa0654d6a6a53eb177c99f42d8)
+++ lams_common/src/java/org/lamsfoundation/lams/learningdesign/ChosenGrouper.java	(.../ChosenGrouper.java)	(revision 7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f)
@@ -132,7 +132,7 @@
     public Group createGroup(Grouping grouping, String name) throws GroupingException
     {
     	int currentSize = grouping.getGroups().size(); 
-    	if ( currentSize == grouping.getMaxNumberOfGroups() ) {
+    	if ( grouping.getMaxNumberOfGroups()!=null && currentSize == grouping.getMaxNumberOfGroups() ) {
     		String error = "Tried to add group "+name+" to grouping "+grouping+". Exceeded max number of groups - current size is "+currentSize;
     		log.error(error); 
     		throw new GroupingException(error);
Index: lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java
===================================================================
diff -u -r978100626b2227b73e36de98f41834d8b8361263 -r7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f
--- lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java	(.../LamsCoreToolService.java)	(revision 978100626b2227b73e36de98f41834d8b8361263)
+++ lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java	(.../LamsCoreToolService.java)	(revision 7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f)
@@ -450,12 +450,12 @@
     
     public String setupURLWithActivityLessonID(Activity activity, Long lessonID, String learnerURL) {
         String url = learnerURL;
-        if ( activity != null ) {
+        if ( url!=null && activity != null ) {
         	url = WebUtil.appendParameterToURL(url,
         		AttributeNames.PARAM_ACTIVITY_ID,
 				activity.getActivityId().toString());
         }
-        if ( lessonID != null ) {
+        if ( url!=null && lessonID != null ) {
         	url = WebUtil.appendParameterToURL(url,
                		AttributeNames.PARAM_LESSON_ID,
                		lessonID.toString());
Index: lams_common/src/java/org/lamsfoundation/lams/util/WebUtil.java
===================================================================
diff -u -r57fbfc34b82cddfb18fc2022aa1cedaf09fa8759 -r7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f
--- lams_common/src/java/org/lamsfoundation/lams/util/WebUtil.java	(.../WebUtil.java)	(revision 57fbfc34b82cddfb18fc2022aa1cedaf09fa8759)
+++ lams_common/src/java/org/lamsfoundation/lams/util/WebUtil.java	(.../WebUtil.java)	(revision 7b5ee95d969b4783ead875cf9eaee6c9f0cbde7f)
@@ -410,7 +410,9 @@
      */
     public static String appendParameterDeliminator(String url)
     {
-        if(StringUtils.containsNone(url,"?"))
+    	if(url==null )
+    		return null;
+    	else if(StringUtils.containsNone(url,"?"))
             return url+"?";
         else
             return url+"&";