* Fix a null ref that causes a stack unwind when crossing borders. Less stack unwinding.. the faster it goes.

* Tweak XEngine so that it's partially functional again.    It's still not great, but basic things work.
(cherry picked from commit 01c3be2746)

OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs

@@ -231,6 +231,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
                 ItemID = ScriptTask.ItemID;
                 AssetID = ScriptTask.AssetID;
             }
+            LocalID = part.LocalId;
 
             PrimName = part.ParentGroup.Name;
             StartParam = startParam;
@@ -1240,4 +1241,4 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             return null;
         }
     }
-}
+}