Thank you for your help. I have a 10 day trial copy of Affinity Designer, which I believe will be perfect for my needs IF I can ever get my head around new tricks.
I can draw the rectangle and select the Fill Tool, however, if I press G my computer makes a really weird clicking noise, just like it does if something is resting on the keys. So that's not an option for me. Dragging the fill tool into the rectangle does nothing, I can't see any colour there, even though I've selected a colour. I find the gradients very simple in FS, and want this to be just as simple.
I'm going to watch the video half a dozen times and see if I can get it sorted.
Many thanks. I prefer to watch the video's so it will be a big help.
Happy New Year to all.