diff --git a/edit.php b/edit.php
index 4443d78..183aa57 100644
--- a/edit.php
+++ b/edit.php
@@ -326,9 +326,13 @@ class KTEditDocumentDispatcher extends KTStandardDispatcher {
 	// to get all fields, we merge repeatedly from KTFieldset::get
 		
 	$field_values = array();
+	
+	// i hate conditionality
+	$condy_fs = array();
 	foreach ($fieldsets as $oFieldSet) {
 	    $fields =& $oFieldSet->getFields();
-	    
+	    $isRealConditional = ($oFieldSet->getIsConditional() && KTMetadataUtil::validateCompleteness($oFieldSet));
+	    $condy_fs[$oFieldSet->getId()] = $isRealConditional;
 	    // FIXME this doesn't handle multi-fieldset fields - are they possible/meaningful?
 	    foreach ($fields as $oField) {
 		$field_values[$oField->getID()] = array($oField, null);
@@ -337,7 +341,11 @@ class KTEditDocumentDispatcher extends KTStandardDispatcher {
 		
 		
 	foreach ($current_md as $oFieldLink) {
+	    // we mustn't copy "old" values for conditional fieldsets.  it breaks unset-set fields.
+        if (!$condy_fs[$field_values[$oFieldLink->getDocumentFieldID()][0]->getParentFieldsetId()]) {
             $field_values[$oFieldLink->getDocumentFieldID()][1] = $oFieldLink->getValue();
+        } 
+        
 	}
 	
 	
diff --git a/lib/documentmanagement/documentutil.inc.php b/lib/documentmanagement/documentutil.inc.php
index 15d44f0..faf620a 100644
--- a/lib/documentmanagement/documentutil.inc.php
+++ b/lib/documentmanagement/documentutil.inc.php
@@ -248,9 +248,10 @@ class KTDocumentUtil {
         foreach ($aFieldsets as $oFieldset) {
             $aFields =& $oFieldset->getFields();
             $aFieldValues = array();
+            $isRealConditional = ($oFieldset->getIsConditional() && KTMetadataUtil::validateCompleteness($oFieldset));
             foreach ($aFields as $oField) {
                 $v = KTUtil::arrayGet($aSimpleMetadata, $oField->getId());
-                if ($oField->getIsMandatory()) {
+                if ($oField->getIsMandatory() && !$isRealConditional) {
                     if (empty($v)) {
                         // XXX: What I'd do for a setdefault...
                         $aFailed["field"][$oField->getId()] = 1;
@@ -260,12 +261,13 @@ class KTDocumentUtil {
                     $aFieldValues[$oField->getId()] = $v;
                 }
             }
-            if ($oFieldset->getIsConditional() && KTMetadataUtil::validateCompleteness($oFieldset)) {
+            
+            if ($isRealConditional) {
                 $res = KTMetadataUtil::getNext($oFieldset, $aFieldValues);
                 if ($res) {
                     $aFailed["fieldset"][$oFieldset->getId()] = 1;
-                }
-            }
+                }             
+            }                        
         }
         if (!empty($aFailed)) {
             return new KTMetadataValidationError($aFailed);
diff --git a/lib/metadata/metadatautil.inc.php b/lib/metadata/metadatautil.inc.php
index c79557b..0f5523f 100644
--- a/lib/metadata/metadatautil.inc.php
+++ b/lib/metadata/metadatautil.inc.php
@@ -88,6 +88,10 @@ class KTMetadataUtil {
                 } else { $oL = $aCurrentSelections[$iThisFieldId]; }
                 
                 $oInstance = KTValueInstance::getByLookupAndParentBehaviour($oL, $oBehaviour);
+                if (is_null($oInstance)) {
+                    // somehow an invalid value hit us here.
+                    continue;
+                }
                 
                 $GLOBALS['default']->log->debug('KTMetadataUtil::_getNextForBehaviour, instance is ' . print_r($oInstance, true));
                 $nextBehaviour = $oInstance->getBehaviourId(); // may be NULL
@@ -169,7 +173,8 @@ class KTMetadataUtil {
         $field = $oMasterField->getId();
         $val = $aCurrentSelections[$field];
         $lookup = MetaData::getByValueAndDocumentField($val, $field);
-        
+
+        //var_dump($lookup); exit(0);
         $oValueInstance = KTValueInstance::getByLookupSingle($lookup);
         if (PEAR::isError($oValueInstance) || is_null($oValueInstance) || ($oValueInstance === false)) { return true; } // throw an error
         $aValues = KTMetadataUtil::_getNextForBehaviour($oValueInstance->getBehaviourId(), $aCurrentSelections);
@@ -528,10 +533,22 @@ class KTMetadataUtil {
         $GLOBALS['default']->log->debug("Number of value instances for master field: $iCount");
         if ($iCount == 0) {
             $GLOBALS['default']->log->debug("Number of value instances for master field is zero, failing");
-            return PEAR::raiseError("Master field has no selectable values");
+            return PEAR::raiseError(_kt("Master field has no values which are assigned to behaviours."));
         }
         $GLOBALS['default']->log->debug("Number of value instances for master field is positive, continuing");
 
+        // fix for KTS-1023
+        // check that each master-field value has a valueinstance assigned.
+        $sTable = KTUtil::getTableName('metadata_lookup');
+        $aQuery = array(
+            "SELECT COUNT(id) AS cnt FROM $sTable WHERE document_field_id = ?",
+            array($iMasterFieldId),
+        );
+        $iValCount = DBUtil::getOneResultKey($aQuery, 'cnt');
+        if ($iValCount != $iCount) {
+            return PEAR::raiseError(sprintf(_kt('%d values for the Master Field are not assigned to behaviours.'), ($iValCount - $iCount)));
+        }
+
         /*
          * Plan: For each behaviour that is assigned on the system,
          * ensure that it allows at least one value instance in each of
@@ -567,14 +584,16 @@ class KTMetadataUtil {
             );
             $aFields = DBUtil::getResultArrayKey($aQuery, 'field_id');
             $GLOBALS['default']->log->debug("   actual fields are " . print_r($aNextFields, true));
+            /*
             foreach ($aNextFields as $iFieldId) {
-                /*if (!in_array($iFieldId, $aFields)) {
+                if (!in_array($iFieldId, $aFields)) {
                     $GLOBALS['default']->log->debug("   field $iFieldId is not included, failing");
                     $oChildField =& DocumentField::get($iFieldId);
                     $sChildFieldName = $oChildField->getName();
                     return PEAR::raiseError("Child field $sChildFieldName of parent field $sParentFieldName has no selectable values in behaviour $sBehaviourHumanName ($sBehaviourName)");
-                }*/
+
             }
+            */            
         }
         $GLOBALS['default']->log->debug("Got through: passed!");
         return true;
diff --git a/lib/metadata/valueinstance.inc.php b/lib/metadata/valueinstance.inc.php
index 95882b7..1cd3ce3 100644
--- a/lib/metadata/valueinstance.inc.php
+++ b/lib/metadata/valueinstance.inc.php
@@ -108,6 +108,9 @@ class KTValueInstance extends KTEntity {
             $GLOBALS['default']->log->error('KTValueInstance::getByLookupAndParentBehaviour: error from db is: ' . print_r($iId, true));
             return $iId;
         }
+        if (is_null($iId)) {
+            return null;
+        }    
         $GLOBALS['default']->log->debug('KTValueInstance::getByLookupAndParentBehaviour: id of instance is ' . $iId);
         if (KTUtil::arrayGet($aOptions, 'ids')) {
             return $iId;
diff --git a/plugins/ktcore/admin/documentFields.php b/plugins/ktcore/admin/documentFields.php
index 28ec9db..dbd8f52 100755
--- a/plugins/ktcore/admin/documentFields.php
+++ b/plugins/ktcore/admin/documentFields.php
@@ -497,7 +497,8 @@ class KTDocumentFieldDispatcher extends KTAdminDispatcher {
 			$res = DBUtil::runQuery($aQuery);	
 			//$this->addInfoMessage('behaviours: ' . print_r($res, true));
 		}
-		
+        KTEntityUtil::clearAllCaches('KTFieldBehaviour');        
+        KTEntityUtil::clearAllCaches('KTValueInstance');     		
         $res = $oFieldset->update();
         if (PEAR::isError($res) || ($res === false)) {
             $this->errorRedirectTo('edit', _kt('Could not stop being conditional'), 'fFieldsetId=' . $oFieldset->getId());
@@ -657,6 +658,7 @@ class KTDocumentFieldDispatcher extends KTAdminDispatcher {
 
     // {{{ do_changeToSimple
     function do_changeToSimple() {
+        $this->startTransaction();
         $oFieldset =& $this->oValidator->validateFieldset($_REQUEST['fFieldsetId']);
         $oFieldset->setIsComplex(false);
         $res = $oFieldset->update();
@@ -664,6 +666,36 @@ class KTDocumentFieldDispatcher extends KTAdminDispatcher {
             'redirect_to' => array('manageConditional', 'fFieldsetId=' . $oFieldset->getId()),
             'message' => _kt('Error changing to simple'),
         ));
+        
+		$aFields = DocumentField::getByFieldset($oFieldset);
+		if (!empty($aFields)) {
+		    $aFieldIds = array();
+			foreach ($aFields as $oField) { $aFieldIds[] = $oField->getId(); }
+			
+			// value instances
+		    $sTable = KTUtil::getTableName('field_value_instances');
+			$aQuery = array(
+			    "DELETE FROM $sTable WHERE field_id IN (" . DBUtil::paramArray($aFieldIds) . ")",
+				$aFieldIds,
+			);
+			$res = DBUtil::runQuery($aQuery);		
+			//$this->addInfoMessage('value instances: ' . print_r($res, true));
+			
+			// behaviours
+		    $sTable = KTUtil::getTableName('field_behaviours');
+			$aQuery = array(
+			    "DELETE FROM $sTable WHERE field_id IN (" . DBUtil::paramArray($aFieldIds) . ")",
+				$aFieldIds,
+			);
+			$res = DBUtil::runQuery($aQuery);	
+			//$this->addInfoMessage('behaviours: ' . print_r($res, true));
+		}        
+        $this->oValidator->notError($res, array(
+            'redirect_to' => array('manageConditional', 'fFieldsetId=' . $oFieldset->getId()),
+            'message' => _kt('Error changing to simple'),
+        ));
+        KTEntityUtil::clearAllCaches('KTFieldBehaviour');        
+        KTEntityUtil::clearAllCaches('KTValueInstance');                
         $this->successRedirectTo('manageConditional', _kt('Changed to simple'), 'fFieldsetId=' . $oFieldset->getId());
     }
     // }}}
diff --git a/templates/ktcore/metadata/conditional/manageConditional.smarty b/templates/ktcore/metadata/conditional/manageConditional.smarty
index b295638..fba016e 100644
--- a/templates/ktcore/metadata/conditional/manageConditional.smarty
+++ b/templates/ktcore/metadata/conditional/manageConditional.smarty
@@ -18,9 +18,9 @@ how the user was allowed to select the specific street (given another field).{/i
 {if $sIncomplete}
 <div class="ktInfo">
 <p>{i18n}This conditional fieldset is marked such that it
-cannot be used.  This happens when the fieldset has been edited and has
-not been set to complete.  Setting the fieldset to complete will do a
-check to see if the fieldset is usable by the user.{/i18n}</p>
+cannot be used.  The system automatically checks whether the fieldset is useable,
+and if not it will prevent it being used in a "conditional" fashion.  Please correct
+the issues identified below.{/i18n}</p>
 </div>
 {/if}