Having moved to version 4.1, I rapidly, and too hastily moved to 4.2.
Unfortunately, I didn't test things properly and I only realised a few days ago that all my old templates and style sheets were broken. The "solution" I found on the web, of "refreshing' the templates, actually installed new templates over the top of the old ones. Not quite what I had in mind.
So, I'm now redesigning/rebuilding new templates … so the site may not be too pretty for awhile.