Aha! thanks, my long press was not long enough!

Store now seems to be working. just tried another alarm, same thing happens - sets for one hour later

I think I'm just going to add things more slowly this time, if you try to add everything you want in one go, it makes it very hard to track down problems

Other issue is that since I completely wiped it, it doesn't react to having the backs changed. I'm not too fussed about different ambiences, but that could be an issue with some other halves