No worries.
Yes, I have downloaded and tried Paint.net, but that's not really suitable as I have a lot of Photoshop files (each with a number of layers) that it can't open.
I'm still using the trial version of Photoshop Elements. It's presently loaded on this new laptop which has been exhibiting some intermittent problems with the display drivers (I think) and, depending on how things go, I may be sending it back before the end of the month. John Lewis have been very good and have offered to replace it or offer a full refund. I'd prefer a replacement, but they no longer stock this model and I don't know if and when they might have it in again.
I did contact Toshiba initially for help and advice but, apart from sending me a software update (which didn't make any difference) they said they can't help because they only guarantee hardware. Any software issues have to be dealt with by their 'premium software associates', and I'm not paying for something to be put right on a three week old computer! Fortunately, John Lewis are light years more supportive than Toshiba.