To access the vessel selection mechanism, you must click on the "play" button.
Select Spacecrafts & Levels
To start a game, you just have to select your level, then launch with the last play button.
You will need to press the Space key, or the screen to start the game.
After waiting, the time of waiting, your spaceships, at the end of your game. You will have to recover manually, your ram released.