Here is the full list of all 7 Project Lounge achievements.
You launched the game at 1AM. Sure you shouldn't be sleeping?
As a host have 7 visitors in your Lounge.
Fall out of the Lounge... and go back to where you came from.
Pick up an object for first time.
As a visitor spawn an item in someone else's Lounge.
Save your very first Lounge.
Press apply button at least once in Options Menu.