When I regenerate a drawing the following appears. So far nothing wrong happened but it can't be good... Command: re REGEN Regenerating model. ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14 ** Undefined block #14