@quasimaddboy neither. They mean the script itself. From the main menu (not the "manage packages" submenu), choose Update (updates the setup script and all installed packages) or Update RetroPie-Setup script (does what it says on the tin, updates just the setup script but not the underlying packages. The first one takes a lot longer.)
You could change your current Ubuntu repository mirror and retry (apt update first). You can use apt-cache policy to check the troublesome packages and see what version are available and from which repository.
I was unable to find held packages, but you got me going in the right direction. For whatever reason, my sources.list file had a comment in it that suggested that because I used a smaller ISO it might not have been the full file. Perhaps a side effect of not allowing online updates during install.
So I got hold of a more 'full' listing of the official sources and ran apt update and it suddenly had way more packages to update and then the install script could find more of what it needed.
Hello, just curious about something I have never done until I have to with a new Pi model or mandatory change, which is start over again with a fresh install. How often do you do this?
Like others here, I also don't do it without good reason, e.g. when I switched from my Pi 3b to my new Pi 4 last spring. I also have customised my installation pretty much, so a new installation would require a good amount of re-configuration, even if most configurations can just be copied over from the old system.
I often wonder if so many updates through a package update eventually cause regressions.
RetroPie is built on Linux which in my long lasting experience doesn't "litter" the system over time as much as Windows does. You usually don't have to clean up or re-install a standard Linux system at all. As far as I can tell as a mere (power) user, RetroPie itself is also pretty neatly designed in the same way, so you shouldn't fear any regressions by just updating it via the RetroPie setup.
All that said, one important thing for any system is to back it up on a regular basis. Apart from failed updates or operating errors, every hardware can break any day for a number of reasons. See the Docs about Making a Backup.
You are truely a hero!
Your solution works very well. I have tested the easyrpg player with my homemade RPG and it works, as far as I have played, without any differences compered to the windows pc version.
@BillyH If you haven't fiddled with the RA's configuration, the save files would stay alonside your ROM files, in the roms sub-folders. Once you access the file shares (\\retropie\roms), you can easily check the contents of those folder and see your save files (most of them have the .srm extension).
@Jareth247 Glad you got it working; I don't think the power switch script had anything to do with it - although the incorrect file that was causing the problem for apt could have been produced by an improper shutdown in the middle of an install operation.