Hello.

Few days ago I discover itch.io and the 1-Button Jam: it makes me join Unity to download their Microgames Tutorial Service and publish the One Button Travel, first exercise. 

http://connect.unity.com/p/unitywalkthrough-5

Hi! And welcome :)

The link you posted here sends me to a game which needs several keys to be played!

Yes, but not really. If the 'unitywalkthrough-5' user wish to realize a better score than 00:50.5, it is only possible using the right arrow key once. This means, that as soon as 'Click here to play' be active and load the game, the time runs and the right arrow key can be pressed: time stops at the right limit. 

Here is another example using a Microgame Tutorial Service: 'upArrowKey', playable with one button only! http://connect.unity.com/p/uparrowkey