I wasn't expecting such a speedy response. Thanks so much for that. I'd already found that I can't set it to centre focus, but I need to hold the Spot AF button for that, but the manual confirms that this is the only option. Thanks so much for the help.

I was able to take it out for a spin this morning and the only qualm I have is that the settings in the view finder can be hard to see in strong light (even with sunglasses taken off).