Again an on-going thanks to all who are offering advice and opinions. It is truly appreciated.
Just to explain a wee bit further, I bought Dorico 4 Pro about a year ago, just as two my my first post-Pandemic musical jobs came in. I didn’t really have time to get up to speed with Dorico, having never used it before, so for these two projects, I persevered with creaky old MakeMusic Finale 2005! It barely runs on Windows 10, and is full of annoying bugs and inconsistencies - but I had spent the previous 16 years learning my around the worst of the horrors, and I needed to be productive in terms of music output from day one.
SO - although I’ve had Dorico 4 Pro for a year or so, and played around with it during “downtime”, to get to know it a bit better, I don’t actually have any serious projects, or preference libraries, or whatever, hanging about.
What I DO have, during that time, is a newly re-formatted PC, now with Windows 11 (and Dorico 4 Pro), which is still more or less squeaky-clean in terms of “clutter”, and running oh so smoothly compared to my previous Windows 10 setup.
SO … YES, I want to upgrade to Dorico 5 Pro, and will. But NO, there is nothing “important” that I need to keep from Dorico 4 Pro. Both those 2022 theatre projects were done in Finale 2005.
THIS is why I think I might be best served, by thoroughly cleaning my machine of Dorico 4 Pro, and then installing Dorico 5 Pro from scratch.
And moreover, it worries me that if I install Dorico 5 Pro, and it relies on the same fonts etc that were installed originally with Dorico 4 Pro - and then uninstall 4 Pro, that some of those shared resources might be deleted by mistake.
IN short … I think I can see what I will be doing over the coming weekend!
And THANK YOU ALL again for your comments and advice! 