Ah, now that's very interesting, thank you. Until this KDP problem arose, I was able to see the prices at the .com Amazon site - now I can't, but I followed your suggestion and checked on .co.uk and the prices are there. Now, can I assume (dangerously!) that my prices are indeed showing up on .com and all the variant sites?
My look inside feature wasn't there, so I emailed them about it. It took them 2 days to reply and another day to fix it, but everything is working now, thankfully. Not having a look inside could only have been hurting my sales.