After editing the parts list, you must hit ok or apply, to save changes. If you decide to right click and open a part from the part lists, the parts list closes without saving changes. It would be nice to prompt the user to save their changes before exiting the parts list. There has been way too many times that I have made a lot of changes to the parts list, and then I decide to right click on a part to open it to make a change to the properties that relate to the parts list, and I forget to hit apply, and the parts list closes without saving.