Unfortunately Amazon won’t let you price books at zero any more (it’s apparently part of Amazon’s so far unsuccessful plan to stop book spam), so while the story’s free on Smashwords it’ll cost money when it goes online in the Kindle store in a few days from now.
The only way to cut the Amazon price below Amazon’s lower limit, which is currently 99 cents, is to sell it more cheaply on another site. Apparently Amazon’s price robot will spot that it’s cheaper and adjust the Amazon price accordingly.
You may think that’s a great big load of pointless faff. I couldn’t possibly comment.
Anyway: here’s a link to Malky’s Bottle of Christmas in as many formats as you could possibly wish for, for the princely sum of no pounds and no pence (unless you’re in America, where the price is no dollars and no cents). There’s a Kindle-friendly .mobi version, an ePub that works in iBooks, even PDF. I hope you like it. Oh, and if you’re the sensitive type, be aware that it’s quite sweary.
I’ve checked it on the Kindle app and it looks okay, but do let me know if the formatting’s gone to pot in your chosen format.