Sunset was released at the end of May, but its sales were underwhelming, so much so that developer Tale of Tales decided to quit commercial game development. It's a shame, as the game was considered to be quite an interesting experience in our review.
The game is now featured in the latest weekly Humble Bundle. You can get the game (and all other titles) for a modest sum. It's not the only interesting game in the collection, as you can also pick up Trine 2 and others for mere pennies.