Thank you for the replies
I've had a go with the starred collections, and it seems to work - pity it takes twice the number of clicks to set them up due to the error messages.
I'll also take a look at the downgrade option, but I think that will have to be another weekend - it doesn't look like a small job!
I wish it were easier to downgrade, though. I've managed to get the jailbreak working and run the kindlet, but it isn't giving me alternative screensavers or fonts.
Still, my main issue is the collections, so thank you both for the help