This is how I do it.
You rename the profile from within vixen, not just manually changing the name in windows explorer etc. There is a Change button at the top of the profile editor screen which allows you to create a renamed copy - keeping the original intact. Then open the sequence and from the Profiles menu Detach the old profile and then Attach the new one. There may be a couple of popup warnings that you need to click Yes/OK to keep your data. Once you have changed all sequences to the new profile then you can delete the old one.