Although with this my new intervention it may be too slow, but if you're planning to do this just once in a time and you don't want to clean DWG from overlaps and other entity types like POLYLINEs and you're confident that your drawing is correct - constant width of walls at openings and frozen doors and other stuff like columns, I suggest that you use my double overkill-restore all selected entities version... Duration of processing now depends of complexity of selection set - the more entities you select, the more processing lasts... But I could think of no better if you're lazy of cleaning and preparing drawing... Beside this you may want to keep original POLYLINEs and LINEs and ARCs as they are with all their properties like colors, widths and so on...
As no one haven't posted some new traps, I consider this is final for now and fixed from undesired bugs...
Kr. M.R.