I have a .cpr that I keep in a project folder with the same name as the template. When I want to change the template I adjust that, check it opens the way I want the template to work then save as template. So if I have some changes based on a live .cpr, that .cpr will have started life as my default studio template. I just save over my template project .cpr, delete all the events in the tracks and any changes I don’t want I reset/remove, to get to the template structure I’m after, check and save over the old template once I’m happy. It’s a bit of a faff, but it works.