I forked my design to a new project file name and on opening the new files, the PCB components had shifted by up to 0.15mm in random directions.  **This is a serious bug and has messed up all of the balanced tracking**.  I have seen this problem a few times in the past but this time it almost got to the point of sending the file off to fabrication before I noticed it.  I had not changed the units from mils to mm as this also causes similar problems, so this is another underlying problem.  **Can we please move this problem to the top of the priority list and get it fixed once and for all** \- components and tracking need to stay exactly where they are placed\.  Even less than 0\.1mm of movement would have wrecked this board from working\.