Thanks, Richard, but we're using the current printer driver for an HP Color LaserJet 3700 TDN PC6. I Emailed some screen prints and the piping model to techsupport@coade.com. The centerline print does OK the first time we print the model, but then acts up on subsequent prints. Also, selecting to show expansion joints SOMETIMES shows rigid elements as well, but not always. Still puzzled.....