minserted blocks?? i got a drawning with minserted blocks, and it is giving me a hard time!! cause I need to use only the lines (ventilation duct trace) which are also inserted with minsert function. although it is not such a big file in size, my CAD gets very, VERY, slow during every operation with this DWG. what can I do to get it simplified?? and to explode minserted blocks? thnx