The add-on seems to work OK but I wasn't able to use it on my site as it is just looks wrong. It is too big and there doesn't seem to be any way for me to adjust the look of it - the size, colour, font, time format etc.

So I've wasted my $15. But, in a way I blame myself. I was wary in the first place about purchasing an add-on for which there isn't a live demo. But I took a chance as it was the only countdown add-on available for 5.7. :-(