I've just had an e-mail saying that the altered/reworked dress works! ("The owner of the frock is very pleased. A fantastic creation!") The relief is huge. Apparently the skirt and petticoat need tightening, as I thought, but that is simply a case of moving the eyes on the waistbands. Oof, I can relax for a moment or two! I'm being sent a photograph, so will post that when it arrives.