--- ibx/trunk/runtime/nongui/IBCustomDataSet.pas	2018/03/15 17:21:13	216
+++ ibx/trunk/runtime/nongui/IBCustomDataSet.pas	2018/03/16 10:27:26	217
@@ -1437,6 +1437,8 @@ begin
   if FDelayTimerValue = AValue then Exit;
   FDelayTimerValue := AValue;
   {$IF FPC_FULLVERSION >= 30002}
+  if (AValue > 0) and not IsMultiThread then
+    IBError(ibxMultiThreadRequired,['TIBQuery/TIBDataset MasterDetailDelay']);
   FTimer.Interval := FDelayTimerValue;
   {$IFEND}
 end;
@@ -1461,6 +1463,7 @@ begin
     if FDelayTimerValue > 0 then
     with FTimer do
     begin
+      CheckSynchronize; {Ensure not waiting on Synchronize}
       if Enabled then
       begin
         StopTimer;
@@ -5095,6 +5098,7 @@ end;
 function TIBDataSetUpdateObject.GetRowsAffected(
   var SelectCount, InsertCount, UpdateCount, DeleteCount: integer): boolean;
 begin
+  Result := true;
   SelectCount := 0;
   InsertCount := 0;
   UpdateCount := 0;