On this occasion I decided that I had best uninstall the software and reinstall it on c:\astronomy\SGP. It had already lost all the settings - which is what led me to investigate. On each occasion before (and on this occasion), it automatically went deeper. It is now in C:\astronomy\SGP\SequenceGeneratorPro… despite my installation instruction. As expected, it lost all the settings for all my equipment and profiles so I shall have to spend some time re-inputting all the data for three cameras and two telescopes, each with different operational configurations (eg sun images where no autoguiding is used).
FWIW we have had no clear evening skies since I was ready for a full autoguiding test over a week ago.
Added later: Fortunately I had saved profiles and sequences in a different folder and they are intact so I should be ‘good to go’.