I posted early yeaterday with the same problem (sorry should of checked
further) copy & paste doesn't solve it permanently for me, but it doesn't
happen to all my visio files (visio 2000 on office 2000). I open them up, it
looks perfect, it then thinks for a minute (litteraly) and spreads all my
shapes, swimlanes, connectors all over the place.
recreating the entire file solves it, but not every time.