Game download problem

Hi,
I'm having problems downloading the TowerFall Ascension game from the store. Actually, I can't even find it with the normal search. After playing a game, Towerfall was shown as a related game. I then saved is as a favourite so I can easily find it. But when I click on "free download", it says that an error occured. I would buy it but I'm afraid I still won't be able to install it.
Is there a trick / is this a known issue?

Thanks!