diff --git a/library/Director/Import/Sync.php b/library/Director/Import/Sync.php
index 28fc4828..a8fe247e 100644
--- a/library/Director/Import/Sync.php
+++ b/library/Director/Import/Sync.php
@@ -4,7 +4,7 @@ namespace Icinga\Module\Director\Import;
 
 use Exception;
 use Icinga\Data\Filter\Filter;
-use Icinga\Module\Director\Import\SyncUtils;
+use Icinga\Module\Director\Db;
 use Icinga\Module\Director\Objects\IcingaObject;
 use Icinga\Module\Director\Objects\ImportSource;
 use Icinga\Module\Director\Objects\IcingaService;
@@ -20,6 +20,11 @@ class Sync
      */
     protected $rule;
 
+    /**
+     * @var Db
+     */
+    protected $db;
+
     /**
      * Related ImportSource objects
      *
@@ -63,6 +68,9 @@ class Sync
 
     protected $syncProperties;
 
+    /**
+     * @var SyncRun
+     */
     protected $run;
 
     protected $runStartTime;
@@ -72,6 +80,8 @@ class Sync
     /**
      * Constructor. No direct initialization allowed right now. Please use one
      * of the available static factory methods
+     *
+     * @param SyncRule $rule
      */
     public function __construct(SyncRule $rule)
     {
@@ -240,6 +250,7 @@ class Sync
         $combinedKey = $this->rule->hasCombinedKey();
 
         foreach ($this->sources as $source) {
+            /** @var ImportSource $source */
             $sourceId = $source->id;
 
             // Provide an alias column for our key. TODO: double-check this!
@@ -544,6 +555,8 @@ class Sync
         $dba = $db->getDbAdapter();
         $dba->beginTransaction();
 
+        $object = null;
+
         try {
             $formerActivityChecksum = Util::hex2binary(
                 $db->getLastActivityChecksum()
@@ -604,7 +617,15 @@ class Sync
 
         } catch (Exception $e) {
             $dba->rollBack();
-            throw $e;
+            if ($object !== null && $object instanceof IcingaObject) {
+                throw new IcingaException(
+                    'Exception while syncing %s %s: %s',
+                    get_class($object), $object->get('object_name'), $e->getMessage(), $e
+                );
+            }
+            else {
+                throw $e;
+            }
         }
 
         return $this->run->id;
diff --git a/library/Director/Objects/IcingaObject.php b/library/Director/Objects/IcingaObject.php
index 0f6d4556..aec05378 100644
--- a/library/Director/Objects/IcingaObject.php
+++ b/library/Director/Objects/IcingaObject.php
@@ -401,7 +401,7 @@ abstract class IcingaObject extends DbObject implements IcingaConfigRenderer
      */
     public function setAssign_filter($filter)
     {
-        if (! $this->supportsAssignments()) {
+        if (! $this->supportsAssignments() && $filter !== null) {
             if ($this->hasProperty('object_type')) {
                 $type = $this->object_type;
             } else {
diff --git a/library/Director/PlainObjectRenderer.php b/library/Director/PlainObjectRenderer.php
index 8267bd4b..11d0eead 100644
--- a/library/Director/PlainObjectRenderer.php
+++ b/library/Director/PlainObjectRenderer.php
@@ -98,14 +98,28 @@ class PlainObjectRenderer
             return self::renderInteger($object);
         } elseif (is_float($object)) {
             return self::renderFloat($object);
+        } elseif (is_object($object) || static::isAssocArray($object)) {
+            return self::renderHash($object, $prefix);
         } elseif (is_array($object)) {
             return self::renderArray($object, $prefix);
-        } elseif (is_object($object)) {
-            return self::renderHash($object, $prefix);
         } elseif (is_string($object)) {
             return self::renderString($object);
         } else {
             return '(UNKNOWN TYPE) ' . var_export($object, 1);
         }
     }
+
+    /**
+     * Check if an array contains assoc keys
+     *
+     * @from https://stackoverflow.com/questions/173400/how-to-check-if-php-array-is-associative-or-sequential
+     * @param $arr
+     * @return bool
+     */
+    protected static function isAssocArray($arr)
+    {
+        if (! is_array($arr)) return false;
+        if (array() === $arr) return false;
+        return array_keys($arr) !== range(0, count($arr) - 1);
+    }
 }