Shotcut version 21.10.31
Start a new project. Put one video clip on the timeline. Make sure to save the project. Close the project. Change the name of the original source file. Start Shotcut again and make sure to load the mlt file of the project. When Shotcut tells you it can’t locate the file either press Search In Folder or double click on the missing file listed to find the file yourself. After pressing Ok on that dialog, Shotcut will load the file with the new name in the timeline but then after a second it will replace the clip on the timeline with the mlt project file for whatever reason.