I saw last night that version 2.3.1 had been released and included some security fixes, so I downloaded it this morning.
I installed the maintenance mode plugin on my test blog to check it out and then put my test blog into maintenance mode while I performed the upgrade. There was a newer version of NoFollow Free available, so I downloaded that for installation at the same time.
The upgrade was very straight forward, backup my database using phpMyAdmin at my website host and then upload the new files. After the files were uploaded, I went to the upgrade page, which confirmed that my database was already up to date.
I replaced the old version of NoFollow Free with the new one and activated it. There was a slight problem with the language variable not being set the first time you go to the options page, but once the options were saved it was fine. I’ve let Michele know about this.
That was it, it was all working, so I turned maintenance mode off and repeated the exercise on my real blog. I may look at customising the screen that maintenance mode shows; on the other hand I don’t expect it to spend much time on, so it might not be worth it.