Have been using PD for many years with no real problems. Just upgraded to 16 and now after editing and I click on Create Disk the undo option is no longer valid. So. if I have made a mistake and click back on edit I can no longer go back and undo. Its geyed out. It works otherwise during editing and the box is ticked for 50 undo's. I have checked my previous version and after click on Create Disk and creating one I can still clcik edit and the undo works, but not on PD16. This is a pain...any ideas.